Project acronym 2DNanoSpec
Project Nanoscale Vibrational Spectroscopy of Sensitive 2D Molecular Materials
Researcher (PI) Renato ZENOBI
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Country Switzerland
Call Details Advanced Grant (AdG), PE4, ERC-2016-ADG
Summary I propose to investigate the nanometer scale organization of delicate 2-dimensional molecular materials using nanoscale vibrational spectroscopy. 2D structures are of great scientific and technological importance, for example as novel materials (graphene, MoS2, WS2, etc.), and in the form of biological membranes and synthetic 2D-polymers. Powerful methods for their analysis and imaging with molecular selectivity and sufficient spatial resolution, however, are lacking. Tip-enhanced Raman spectroscopy (TERS) allows label-free spectroscopic identification of molecular species, with ≈10 nm spatial resolution, and with single molecule sensitivity for strong Raman scatterers. So far, however, TERS is not being carried out in liquids, which is the natural environment for membranes, and its application to poor Raman scatterers such as components of 2D polymers, lipids, or other membrane compounds (proteins, sugars) is difficult. TERS has the potential to overcome the restrictions of other optical/spectroscopic methods to study 2D materials, namely (i) insufficient spatial resolution of diffraction-limited optical methods; (ii) the need for labelling for all methods relying on fluorescence; and (iii) the inability of some methods to work in liquids. I propose to address a number of scientific questions associated with the spatial organization, and the occurrence of defects in sensitive 2D molecular materials. The success of these studies will also rely critically on technical innovations of TERS that notably address the problem of energy dissipation. This will for the first time allow its application to study of complex, delicate 2D molecular systems without photochemical damage.
Summary
I propose to investigate the nanometer scale organization of delicate 2-dimensional molecular materials using nanoscale vibrational spectroscopy. 2D structures are of great scientific and technological importance, for example as novel materials (graphene, MoS2, WS2, etc.), and in the form of biological membranes and synthetic 2D-polymers. Powerful methods for their analysis and imaging with molecular selectivity and sufficient spatial resolution, however, are lacking. Tip-enhanced Raman spectroscopy (TERS) allows label-free spectroscopic identification of molecular species, with ≈10 nm spatial resolution, and with single molecule sensitivity for strong Raman scatterers. So far, however, TERS is not being carried out in liquids, which is the natural environment for membranes, and its application to poor Raman scatterers such as components of 2D polymers, lipids, or other membrane compounds (proteins, sugars) is difficult. TERS has the potential to overcome the restrictions of other optical/spectroscopic methods to study 2D materials, namely (i) insufficient spatial resolution of diffraction-limited optical methods; (ii) the need for labelling for all methods relying on fluorescence; and (iii) the inability of some methods to work in liquids. I propose to address a number of scientific questions associated with the spatial organization, and the occurrence of defects in sensitive 2D molecular materials. The success of these studies will also rely critically on technical innovations of TERS that notably address the problem of energy dissipation. This will for the first time allow its application to study of complex, delicate 2D molecular systems without photochemical damage.
Max ERC Funding
2 311 696 €
Duration
Start date: 2017-09-01, End date: 2022-08-31
Project acronym 3DIMAGE
Project 3D Imaging Across Lengthscales: From Atoms to Grains
Researcher (PI) Paul Anthony Midgley
Host Institution (HI) THE CHANCELLOR MASTERS AND SCHOLARS OF THE UNIVERSITY OF CAMBRIDGE
Country United Kingdom
Call Details Advanced Grant (AdG), PE4, ERC-2011-ADG_20110209
Summary "Understanding structure-property relationships across lengthscales is key to the design of functional and structural materials and devices. Moreover, the complexity of modern devices extends to three dimensions and as such 3D characterization is required across those lengthscales to provide a complete understanding and enable improvement in the material’s physical and chemical behaviour. 3D imaging and analysis from the atomic scale through to granular microstructure is proposed through the development of electron tomography using (S)TEM, and ‘dual beam’ SEM-FIB, techniques offering complementary approaches to 3D imaging across lengthscales stretching over 5 orders of magnitude.
We propose to extend tomography to include novel methods to determine atom positions in 3D with approaches incorporating new reconstruction algorithms, image processing and complementary nano-diffraction techniques. At the nanoscale, true 3D nano-metrology of morphology and composition is a key objective of the project, minimizing reconstruction and visualization artefacts. Mapping strain and optical properties in 3D are ambitious and exciting challenges that will yield new information at the nanoscale. Using the SEM-FIB, 3D ‘mesoscale’ structures will be revealed: morphology, crystallography and composition can be mapped simultaneously, with ~5nm resolution and over volumes too large to tackle by (S)TEM and too small for most x-ray techniques. In parallel, we will apply 3D imaging to a wide variety of key materials including heterogeneous catalysts, aerospace alloys, biomaterials, photovoltaic materials, and novel semiconductors.
We will collaborate with many departments in Cambridge and institutes worldwide. The personnel on the proposal will cover all aspects of the tomography proposed using high-end TEMs, including an aberration-corrected Titan, and a Helios dual beam. Importantly, a postdoc is dedicated to developing new algorithms for reconstruction, image and spectral processing."
Summary
"Understanding structure-property relationships across lengthscales is key to the design of functional and structural materials and devices. Moreover, the complexity of modern devices extends to three dimensions and as such 3D characterization is required across those lengthscales to provide a complete understanding and enable improvement in the material’s physical and chemical behaviour. 3D imaging and analysis from the atomic scale through to granular microstructure is proposed through the development of electron tomography using (S)TEM, and ‘dual beam’ SEM-FIB, techniques offering complementary approaches to 3D imaging across lengthscales stretching over 5 orders of magnitude.
We propose to extend tomography to include novel methods to determine atom positions in 3D with approaches incorporating new reconstruction algorithms, image processing and complementary nano-diffraction techniques. At the nanoscale, true 3D nano-metrology of morphology and composition is a key objective of the project, minimizing reconstruction and visualization artefacts. Mapping strain and optical properties in 3D are ambitious and exciting challenges that will yield new information at the nanoscale. Using the SEM-FIB, 3D ‘mesoscale’ structures will be revealed: morphology, crystallography and composition can be mapped simultaneously, with ~5nm resolution and over volumes too large to tackle by (S)TEM and too small for most x-ray techniques. In parallel, we will apply 3D imaging to a wide variety of key materials including heterogeneous catalysts, aerospace alloys, biomaterials, photovoltaic materials, and novel semiconductors.
We will collaborate with many departments in Cambridge and institutes worldwide. The personnel on the proposal will cover all aspects of the tomography proposed using high-end TEMs, including an aberration-corrected Titan, and a Helios dual beam. Importantly, a postdoc is dedicated to developing new algorithms for reconstruction, image and spectral processing."
Max ERC Funding
2 337 330 €
Duration
Start date: 2012-01-01, End date: 2017-12-31
Project acronym 3DNANOMECH
Project Three-dimensional molecular resolution mapping of soft matter-liquid interfaces
Researcher (PI) Ricardo Garcia
Host Institution (HI) AGENCIA ESTATAL CONSEJO SUPERIOR DEINVESTIGACIONES CIENTIFICAS
Country Spain
Call Details Advanced Grant (AdG), PE4, ERC-2013-ADG
Summary Optical, electron and probe microscopes are enabling tools for discoveries and knowledge generation in nanoscale sicence and technology. High resolution –nanoscale or molecular-, noninvasive and label-free imaging of three-dimensional soft matter-liquid interfaces has not been achieved by any microscopy method.
Force microscopy (AFM) is considered the second most relevant advance in materials science since 1960. Despite its impressive range of applications, the technique has some key limitations. Force microscopy has not three dimensional depth. What lies above or in the subsurface is not readily characterized.
3DNanoMech proposes to design, build and operate a high speed force-based method for the three-dimensional characterization soft matter-liquid interfaces (3D AFM). The microscope will combine a detection method based on force perturbations, adaptive algorithms, high speed piezo actuators and quantitative-oriented multifrequency approaches. The development of the microscope cannot be separated from its applications: imaging the error-free DNA repair and to understand the relationship existing between the nanomechanical properties and the malignancy of cancer cells. Those problems encompass the different spatial –molecular-nano-mesoscopic- and time –milli to seconds- scales of the instrument.
In short, 3DNanoMech aims to image, map and measure with picoNewton, millisecond and angstrom resolution soft matter surfaces and interfaces in liquid. The long-term vision of 3DNanoMech is to replace models or computer animations of bimolecular-liquid interfaces by real time, molecular resolution maps of properties and processes.
Summary
Optical, electron and probe microscopes are enabling tools for discoveries and knowledge generation in nanoscale sicence and technology. High resolution –nanoscale or molecular-, noninvasive and label-free imaging of three-dimensional soft matter-liquid interfaces has not been achieved by any microscopy method.
Force microscopy (AFM) is considered the second most relevant advance in materials science since 1960. Despite its impressive range of applications, the technique has some key limitations. Force microscopy has not three dimensional depth. What lies above or in the subsurface is not readily characterized.
3DNanoMech proposes to design, build and operate a high speed force-based method for the three-dimensional characterization soft matter-liquid interfaces (3D AFM). The microscope will combine a detection method based on force perturbations, adaptive algorithms, high speed piezo actuators and quantitative-oriented multifrequency approaches. The development of the microscope cannot be separated from its applications: imaging the error-free DNA repair and to understand the relationship existing between the nanomechanical properties and the malignancy of cancer cells. Those problems encompass the different spatial –molecular-nano-mesoscopic- and time –milli to seconds- scales of the instrument.
In short, 3DNanoMech aims to image, map and measure with picoNewton, millisecond and angstrom resolution soft matter surfaces and interfaces in liquid. The long-term vision of 3DNanoMech is to replace models or computer animations of bimolecular-liquid interfaces by real time, molecular resolution maps of properties and processes.
Max ERC Funding
2 499 928 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym ABACUS
Project Ab-initio adiabatic-connection curves for density-functional analysis and construction
Researcher (PI) Trygve Ulf Helgaker
Host Institution (HI) UNIVERSITETET I OSLO
Country Norway
Call Details Advanced Grant (AdG), PE4, ERC-2010-AdG_20100224
Summary Quantum chemistry provides two approaches to molecular electronic-structure calculations: the systematically refinable but expensive many-body wave-function methods and the inexpensive but not systematically refinable Kohn Sham method of density-functional theory (DFT). The accuracy of Kohn Sham calculations is determined by the quality of the exchange correlation functional, from which the effects of exchange and correlation among the electrons are extracted using the density rather than the wave function. However, the exact exchange correlation functional is unknown—instead, many approximate forms have been developed, by fitting to experimental data or by satisfying exact relations. Here, a new approach to density-functional analysis and construction is proposed: the Lieb variation principle, usually regarded as conceptually important but impracticable. By invoking the Lieb principle, it becomes possible to approach the development of approximate functionals in a novel manner, being directly guided by the behaviour of exact functional, accurately calculated for a wide variety of chemical systems. In particular, this principle will be used to calculate ab-initio adiabatic connection curves, studying the exchange correlation functional for a fixed density as the electronic interactions are turned on from zero to one. Pilot calculations have indicated the feasibility of this approach in simple cases—here, a comprehensive set of adiabatic-connection curves will be generated and utilized for calibration, construction, and analysis of density functionals, the objective being to produce improved functionals for Kohn Sham calculations by modelling or fitting such curves. The ABACUS approach will be particularly important in cases where little experimental information is available—for example, for understanding and modelling the behaviour of the exchange correlation functional in electromagnetic fields.
Summary
Quantum chemistry provides two approaches to molecular electronic-structure calculations: the systematically refinable but expensive many-body wave-function methods and the inexpensive but not systematically refinable Kohn Sham method of density-functional theory (DFT). The accuracy of Kohn Sham calculations is determined by the quality of the exchange correlation functional, from which the effects of exchange and correlation among the electrons are extracted using the density rather than the wave function. However, the exact exchange correlation functional is unknown—instead, many approximate forms have been developed, by fitting to experimental data or by satisfying exact relations. Here, a new approach to density-functional analysis and construction is proposed: the Lieb variation principle, usually regarded as conceptually important but impracticable. By invoking the Lieb principle, it becomes possible to approach the development of approximate functionals in a novel manner, being directly guided by the behaviour of exact functional, accurately calculated for a wide variety of chemical systems. In particular, this principle will be used to calculate ab-initio adiabatic connection curves, studying the exchange correlation functional for a fixed density as the electronic interactions are turned on from zero to one. Pilot calculations have indicated the feasibility of this approach in simple cases—here, a comprehensive set of adiabatic-connection curves will be generated and utilized for calibration, construction, and analysis of density functionals, the objective being to produce improved functionals for Kohn Sham calculations by modelling or fitting such curves. The ABACUS approach will be particularly important in cases where little experimental information is available—for example, for understanding and modelling the behaviour of the exchange correlation functional in electromagnetic fields.
Max ERC Funding
2 017 932 €
Duration
Start date: 2011-03-01, End date: 2016-02-29
Project acronym AFTERTHEGOLDRUSH
Project Addressing global sustainability challenges by changing perceptions in catalyst design
Researcher (PI) Graham John Hutchings
Host Institution (HI) CARDIFF UNIVERSITY
Country United Kingdom
Call Details Advanced Grant (AdG), PE4, ERC-2011-ADG_20110209
Summary One of the greatest challenges facing society is the sustainability of resources. At present, a step change in the sustainable use of resources is needed and catalysis lies at the heart of the solution by providing new routes to carbon dioxide mitigation, energy security and water conservation. It is clear that new high efficiency game-changing catalysts are required to meet the challenge. This proposal will focus on excellence in catalyst design by learning from recent step change advances in gold catalysis by challenging perceptions. Intense interest in gold catalysts over the past two decades has accelerated our understanding of gold particle-size effects, gold-support and gold-metal interactions, the interchange between atomic and ionic gold species, and the role of the gold-support interface in creating and maintaining catalytic activity. The field has also driven the development of cutting-edge techniques, particularly in microscopy and transient kinetics, providing detailed structural characterisation on the nano-scale and probing the short-range and often short-lived interactions. By comparison, our understanding of other metal catalysts has remained relatively static.
The proposed programme will engender a step change in the design of supported-metal catalysts, by exploiting the learning and the techniques emerging from gold catalysis. The research will be set out in two themes. In Theme 1 two established key grand challenges will be attacked; namely, energy vectors and greenhouse gas control. Theme 2 will address two new and emerging grand challenges in catalysis namely the effective low temperature activation of primary carbon hydrogen bonds and CO2 utilisation where instead of treating CO2 as a thermodynamic endpoint, the aim will be to re-use it as a feedstock for bulk chemical and fuel production. The legacy of the research will be the development of a new catalyst design approach that will provide a tool box for future catalyst development.
Summary
One of the greatest challenges facing society is the sustainability of resources. At present, a step change in the sustainable use of resources is needed and catalysis lies at the heart of the solution by providing new routes to carbon dioxide mitigation, energy security and water conservation. It is clear that new high efficiency game-changing catalysts are required to meet the challenge. This proposal will focus on excellence in catalyst design by learning from recent step change advances in gold catalysis by challenging perceptions. Intense interest in gold catalysts over the past two decades has accelerated our understanding of gold particle-size effects, gold-support and gold-metal interactions, the interchange between atomic and ionic gold species, and the role of the gold-support interface in creating and maintaining catalytic activity. The field has also driven the development of cutting-edge techniques, particularly in microscopy and transient kinetics, providing detailed structural characterisation on the nano-scale and probing the short-range and often short-lived interactions. By comparison, our understanding of other metal catalysts has remained relatively static.
The proposed programme will engender a step change in the design of supported-metal catalysts, by exploiting the learning and the techniques emerging from gold catalysis. The research will be set out in two themes. In Theme 1 two established key grand challenges will be attacked; namely, energy vectors and greenhouse gas control. Theme 2 will address two new and emerging grand challenges in catalysis namely the effective low temperature activation of primary carbon hydrogen bonds and CO2 utilisation where instead of treating CO2 as a thermodynamic endpoint, the aim will be to re-use it as a feedstock for bulk chemical and fuel production. The legacy of the research will be the development of a new catalyst design approach that will provide a tool box for future catalyst development.
Max ERC Funding
2 279 785 €
Duration
Start date: 2012-04-01, End date: 2017-03-31
Project acronym AQUACHIRAL
Project Chiral aqueous-phase chemistry
Researcher (PI) Bernd Winter
Host Institution (HI) MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV
Country Germany
Call Details Advanced Grant (AdG), PE4, ERC-2019-ADG
Summary Most chemical reactions in lifeforms take place in aqueous environments and probing biochemical molecules and their reactions in the aqueous phase is indispensable for advancing fundamental and applied science. Equally, intermolecular effects involving chiral complexes are highly relevant to life sciences, where hydration and chiral recognition are fundamental biochemical processes, typically occurring at aqueous interfaces. All of these processes are driven by electronic structure interactions with water molecules and are intimately connected with aqueous-phase electron binding energies. The prime experimental tool to access these properties is photoelectron spectroscopy (PES). With the recent invention of liquid-microjet-(LJ) PES, compatible with highly volatile liquid water and aqueous solutions, this technique has significantly contributed to modern water research, providing important insights into formerly elusive water properties, such as absolute energetics and solute interfacial distributions.
I propose to explore chirality in aqueous solution using a novel aspect of photoelectron emission: photoelectron circular dichroism (PECD). It is site-specific and sensitive to chemical environment and structure. Furthermore, PECD exceeds absorption-based chiroptical signals by orders of magnitude, allowing application to dilute samples, potentially including interfacial layers, akin to PES. PECD has been demonstrated for isolated chiral molecules and clusters, and measurement of PECD effects in aqueous solution would mark a scientific breakthrough.
The aim of AQUACHIRAL is to combine LJ-PES with PECD to (1) probe aqueous-phase chirality using enantioselective electronic-structure fingerprints of solutes and to (2) follow the stereochemistry of prominent chemical reactions in aqueous solution, e.g. slow glucose mutarotation. To achieve this, experimental technology must be extended, with novel liquid jets and electron detection systems being developed and optimized.
Summary
Most chemical reactions in lifeforms take place in aqueous environments and probing biochemical molecules and their reactions in the aqueous phase is indispensable for advancing fundamental and applied science. Equally, intermolecular effects involving chiral complexes are highly relevant to life sciences, where hydration and chiral recognition are fundamental biochemical processes, typically occurring at aqueous interfaces. All of these processes are driven by electronic structure interactions with water molecules and are intimately connected with aqueous-phase electron binding energies. The prime experimental tool to access these properties is photoelectron spectroscopy (PES). With the recent invention of liquid-microjet-(LJ) PES, compatible with highly volatile liquid water and aqueous solutions, this technique has significantly contributed to modern water research, providing important insights into formerly elusive water properties, such as absolute energetics and solute interfacial distributions.
I propose to explore chirality in aqueous solution using a novel aspect of photoelectron emission: photoelectron circular dichroism (PECD). It is site-specific and sensitive to chemical environment and structure. Furthermore, PECD exceeds absorption-based chiroptical signals by orders of magnitude, allowing application to dilute samples, potentially including interfacial layers, akin to PES. PECD has been demonstrated for isolated chiral molecules and clusters, and measurement of PECD effects in aqueous solution would mark a scientific breakthrough.
The aim of AQUACHIRAL is to combine LJ-PES with PECD to (1) probe aqueous-phase chirality using enantioselective electronic-structure fingerprints of solutes and to (2) follow the stereochemistry of prominent chemical reactions in aqueous solution, e.g. slow glucose mutarotation. To achieve this, experimental technology must be extended, with novel liquid jets and electron detection systems being developed and optimized.
Max ERC Funding
2 490 250 €
Duration
Start date: 2021-01-01, End date: 2025-12-31
Project acronym ASC3
Project Asymmetric Cluster Catalysis & Chemistry
Researcher (PI) Ulrich Kaspar Heiz
Host Institution (HI) TECHNISCHE UNIVERSITAET MUENCHEN
Country Germany
Call Details Advanced Grant (AdG), PE4, ERC-2009-AdG
Summary The objective of the present scientific proposal is the implementation of a novel approach in selective and asymmetric heterogeneous catalysis. We aim to exploit the structure and chirality of small, supported metal and bimetal clusters for triggering selective and enantioselective reactions. Our Ansatz is beyond doubt of fundamental nature. Although chemistry and in particular catalysis evolved on a largely empirical basis in the past, we strongly believe the complexity of the challenges at hand to make this a less ideal approach. In consequence, developing selective and asymmetric cluster catalysis will be based on a detailed molecular understanding and will not only require intense methodological developments for the synthesis and characterization of asymmetric catalysts and the detection of chiral and isomeric product molecules but also make use of innovative basic science in the fields of surface chemistry, cluster science, spectroscopy and kinetics. As complex as the involved challenges are, we aim at mastering the following ground-breaking steps: (a) development of cutting-edge spectroscopic methodologies for the isomer and enantiomer sensitive in situ detection of product molecules. (b) preparation and characterization of isomer- and enantioselective heterogeneous catalysts based on chiral metal clusters or molecule-cluster-complexes. (c) investigations of the selectivity and enantioselectivity of cluster based heterogeneous catalysts and formulation of concepts for understanding the observed selective and asymmetric chemistry.
Besides the importance of the science carried out within this proposal, the proposed experimental methodology will also open up opportunities in other fields of chemistry like catalysis, analytical chemistry, spectroscopy, surface science, and nanomaterials.
Summary
The objective of the present scientific proposal is the implementation of a novel approach in selective and asymmetric heterogeneous catalysis. We aim to exploit the structure and chirality of small, supported metal and bimetal clusters for triggering selective and enantioselective reactions. Our Ansatz is beyond doubt of fundamental nature. Although chemistry and in particular catalysis evolved on a largely empirical basis in the past, we strongly believe the complexity of the challenges at hand to make this a less ideal approach. In consequence, developing selective and asymmetric cluster catalysis will be based on a detailed molecular understanding and will not only require intense methodological developments for the synthesis and characterization of asymmetric catalysts and the detection of chiral and isomeric product molecules but also make use of innovative basic science in the fields of surface chemistry, cluster science, spectroscopy and kinetics. As complex as the involved challenges are, we aim at mastering the following ground-breaking steps: (a) development of cutting-edge spectroscopic methodologies for the isomer and enantiomer sensitive in situ detection of product molecules. (b) preparation and characterization of isomer- and enantioselective heterogeneous catalysts based on chiral metal clusters or molecule-cluster-complexes. (c) investigations of the selectivity and enantioselectivity of cluster based heterogeneous catalysts and formulation of concepts for understanding the observed selective and asymmetric chemistry.
Besides the importance of the science carried out within this proposal, the proposed experimental methodology will also open up opportunities in other fields of chemistry like catalysis, analytical chemistry, spectroscopy, surface science, and nanomaterials.
Max ERC Funding
2 301 600 €
Duration
Start date: 2010-04-01, End date: 2015-03-31
Project acronym ASES
Project "Advancing computational chemistry with new accurate, robust and scalable electronic structure methods"
Researcher (PI) Hans-Joachim Werner
Host Institution (HI) UNIVERSITY OF STUTTGART
Country Germany
Call Details Advanced Grant (AdG), PE4, ERC-2012-ADG_20120216
Summary "The objective of this proposal is to tackle two of the greatest challenges in quantum chemistry: (i) extending the applicability of highly accurate wave function methods to large molecular systems, and (ii) developing accurate and robust multi-reference methods that can be used for studying important but very difficult problems in transition metal chemistry, catalysis, and photochemistry. Solutions to these problems have now come within reach due to three advances we recently reported: first, the steep scaling of the computational cost with molecular size can be reduced to linear by exploiting the short-range character of electron correlation (local correlation methods). Second, the accuracy, efficiency, and robustness of these local correlation methods can be strongly improved by new tensor decomposition approaches and the inclusion of terms depending explicitly on the inter-electronic distances (F12 methods). Third, the development of highly complex electronic structure theories can be greatly facilitated and accelerated by new automated tensor network evaluation techniques. We are certain that by combining and generalizing these advances the long-standing problems (i) and (ii) can be solved. We will focus especially on highly scalable algorithms in order to use massively parallel computer systems efficiently. For linear-scaling methods this means that the size of the molecules that can be treated in a fixed time will grow linearly with the number of available processors. We will furthermore explore new multi-reference ansätze and implement analytical energy gradients and response properties for local methods. Hybrid and embedding methods to account for solvent and environment effects will also be investigated. It is our priority to make our new methods as easy to use, robust, and widely applicable as possible. We believe that they will open entirely new horizons for innumerable applications in chemistry, physics, biology, and materials science."
Summary
"The objective of this proposal is to tackle two of the greatest challenges in quantum chemistry: (i) extending the applicability of highly accurate wave function methods to large molecular systems, and (ii) developing accurate and robust multi-reference methods that can be used for studying important but very difficult problems in transition metal chemistry, catalysis, and photochemistry. Solutions to these problems have now come within reach due to three advances we recently reported: first, the steep scaling of the computational cost with molecular size can be reduced to linear by exploiting the short-range character of electron correlation (local correlation methods). Second, the accuracy, efficiency, and robustness of these local correlation methods can be strongly improved by new tensor decomposition approaches and the inclusion of terms depending explicitly on the inter-electronic distances (F12 methods). Third, the development of highly complex electronic structure theories can be greatly facilitated and accelerated by new automated tensor network evaluation techniques. We are certain that by combining and generalizing these advances the long-standing problems (i) and (ii) can be solved. We will focus especially on highly scalable algorithms in order to use massively parallel computer systems efficiently. For linear-scaling methods this means that the size of the molecules that can be treated in a fixed time will grow linearly with the number of available processors. We will furthermore explore new multi-reference ansätze and implement analytical energy gradients and response properties for local methods. Hybrid and embedding methods to account for solvent and environment effects will also be investigated. It is our priority to make our new methods as easy to use, robust, and widely applicable as possible. We believe that they will open entirely new horizons for innumerable applications in chemistry, physics, biology, and materials science."
Max ERC Funding
2 454 000 €
Duration
Start date: 2013-02-01, End date: 2018-01-31
Project acronym BALANCE
Project Mapping Dispersion Spectroscopically in Large Gas-Phase Molecular Ions
Researcher (PI) Peter CHEN
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Country Switzerland
Call Details Advanced Grant (AdG), PE4, ERC-2018-ADG
Summary We use IR spectroscopy of trapped ions in a cryogenic FT-ICR spectrometer to probe non-covalent, “dispersion” interactions in large, gas-phase molecular ions. We will measure conformational equilibria by N-H frequency shifts, and correlate gas-phase IR frequency to the N-H-N bond angle in an ionic H-bond. Substituents on “onium” cations can adopt various conformations, whose energies map interaction potentials. Substituents on their proton-bound dimers interact non-covalently through dispersion forces, whose quantitative evaluation in large molecules has remained difficult despite dispersion becoming increasingly cited as a design principle in the construction of catalysts and materials. The non-covalent interactions bend the N-H-N bond, leading to large shifts in the IR frequency. The proton-bound dimer acts like a molecular balance where the non-covalent interaction, is set against the bending potential in an ionic hydrogen bond. Despite encouragingly accurate calculations for small molecules, experimental benchmarks for large molecules in the gas phase remain scarce, and there is evidence that the good results for small molecules may not extrapolate reliably to large molecules. The present proposal introduces a new experimental probe of non-covalent interactions, providing a sensitive test of the diverging results coming from various computational methods and other experiments. The experiment must be done on isolated molecules in the gas phase, as previous work has shown that solvation substantially cancels out the attractive potential. Accordingly, the proposed experimental design, which involves a custom-built spectrometer, newly available tunable IR sources, chemical synthesis of custom substrates, and quantum calculations up to coupled-cluster levels of theory, showcases how an interdisciplinary approach combining physical and organic chemistry can solve a fundamental problem that impacts how we understand steric effects in organic chemistry.
Summary
We use IR spectroscopy of trapped ions in a cryogenic FT-ICR spectrometer to probe non-covalent, “dispersion” interactions in large, gas-phase molecular ions. We will measure conformational equilibria by N-H frequency shifts, and correlate gas-phase IR frequency to the N-H-N bond angle in an ionic H-bond. Substituents on “onium” cations can adopt various conformations, whose energies map interaction potentials. Substituents on their proton-bound dimers interact non-covalently through dispersion forces, whose quantitative evaluation in large molecules has remained difficult despite dispersion becoming increasingly cited as a design principle in the construction of catalysts and materials. The non-covalent interactions bend the N-H-N bond, leading to large shifts in the IR frequency. The proton-bound dimer acts like a molecular balance where the non-covalent interaction, is set against the bending potential in an ionic hydrogen bond. Despite encouragingly accurate calculations for small molecules, experimental benchmarks for large molecules in the gas phase remain scarce, and there is evidence that the good results for small molecules may not extrapolate reliably to large molecules. The present proposal introduces a new experimental probe of non-covalent interactions, providing a sensitive test of the diverging results coming from various computational methods and other experiments. The experiment must be done on isolated molecules in the gas phase, as previous work has shown that solvation substantially cancels out the attractive potential. Accordingly, the proposed experimental design, which involves a custom-built spectrometer, newly available tunable IR sources, chemical synthesis of custom substrates, and quantum calculations up to coupled-cluster levels of theory, showcases how an interdisciplinary approach combining physical and organic chemistry can solve a fundamental problem that impacts how we understand steric effects in organic chemistry.
Max ERC Funding
2 446 125 €
Duration
Start date: 2019-05-01, End date: 2024-04-30
Project acronym BATNMR
Project Development and Application of New NMR Methods for Studying Interphases and Interfaces in Batteries
Researcher (PI) Clare GREY
Host Institution (HI) THE CHANCELLOR MASTERS AND SCHOLARS OF THE UNIVERSITY OF CAMBRIDGE
Country United Kingdom
Call Details Advanced Grant (AdG), PE4, ERC-2018-ADG
Summary The development of longer lasting, higher energy density and cheaper rechargeable batteries represents one of the major technological challenges of our society, batteries representing the limiting components in the shift from gasoline-powered to electric vehicles. They are also required to enable the use of more (typically intermittent) renewable energy, to balance demand with generation. This proposal seeks to develop and apply new NMR metrologies to determine the structure and dynamics of the multiple electrode-electrolyte interfaces and interphases that are present in these batteries, and how they evolve during battery cycling. New dynamic nuclear polarization (DNP) techniques will be exploited to extract structural information about the interface between the battery electrode and the passivating layers that grow on the electrode materials (the solid electrolyte interphase, SEI) and that are inherent to the stability of the batteries. The role of the SEI (and ceramic interfaces) in controlling lithium metal dendrite growth will be determined in liquid based and all solid state batteries.
New DNP approaches will be developed that are compatible with the heterogeneous and reactive species that are present in conventional, all-solid state, Li-air and redox flow batteries. Method development will run in parallel with the use of DNP approaches to determine the structures of the various battery interfaces and interphases, testing the stability of conventional biradicals in these harsh oxidizing and reducing conditions, modifying the experimental approaches where appropriate. The final result will be a significantly improved understanding of the structures of these phases and how they evolve on cycling, coupled with strategies for designing improved SEI structures. The nature of the interface between a lithium metal dendrite and ceramic composite will be determined, providing much needed insight into how these (unwanted) dendrites grow in all solid state batteries. DNP approaches coupled with electron spin resonance will be use, where possible in situ, to determine the reaction mechanisms of organic molecules such as quinones in organic-based redox flow batteries in order to help prevent degradation of the electrochemically active species.
This proposal involves NMR method development specifically designed to explore a variety of battery chemistries. Thus, this proposal is interdisciplinary, containing both a strong emphasis on materials characterization, electrochemistry and electronic structures of materials, interfaces and nanoparticles, and on analytical and physical chemistry. Some of the methodology will be applicable to other materials and systems including (for example) other electrochemical technologies such as fuel cells and solar fuels and the study of catalysts (to probe surface structure).
Summary
The development of longer lasting, higher energy density and cheaper rechargeable batteries represents one of the major technological challenges of our society, batteries representing the limiting components in the shift from gasoline-powered to electric vehicles. They are also required to enable the use of more (typically intermittent) renewable energy, to balance demand with generation. This proposal seeks to develop and apply new NMR metrologies to determine the structure and dynamics of the multiple electrode-electrolyte interfaces and interphases that are present in these batteries, and how they evolve during battery cycling. New dynamic nuclear polarization (DNP) techniques will be exploited to extract structural information about the interface between the battery electrode and the passivating layers that grow on the electrode materials (the solid electrolyte interphase, SEI) and that are inherent to the stability of the batteries. The role of the SEI (and ceramic interfaces) in controlling lithium metal dendrite growth will be determined in liquid based and all solid state batteries.
New DNP approaches will be developed that are compatible with the heterogeneous and reactive species that are present in conventional, all-solid state, Li-air and redox flow batteries. Method development will run in parallel with the use of DNP approaches to determine the structures of the various battery interfaces and interphases, testing the stability of conventional biradicals in these harsh oxidizing and reducing conditions, modifying the experimental approaches where appropriate. The final result will be a significantly improved understanding of the structures of these phases and how they evolve on cycling, coupled with strategies for designing improved SEI structures. The nature of the interface between a lithium metal dendrite and ceramic composite will be determined, providing much needed insight into how these (unwanted) dendrites grow in all solid state batteries. DNP approaches coupled with electron spin resonance will be use, where possible in situ, to determine the reaction mechanisms of organic molecules such as quinones in organic-based redox flow batteries in order to help prevent degradation of the electrochemically active species.
This proposal involves NMR method development specifically designed to explore a variety of battery chemistries. Thus, this proposal is interdisciplinary, containing both a strong emphasis on materials characterization, electrochemistry and electronic structures of materials, interfaces and nanoparticles, and on analytical and physical chemistry. Some of the methodology will be applicable to other materials and systems including (for example) other electrochemical technologies such as fuel cells and solar fuels and the study of catalysts (to probe surface structure).
Max ERC Funding
3 498 219 €
Duration
Start date: 2019-10-01, End date: 2024-09-30
