Professor of Chemistry

[email protected]Office Information:

2000D Chemistry

930 N University

phone: 734.763.8012

Applied Physics Program; Physical Chemistry

Education/Degree:

Ph.D. Hebrew University of Jerusalem### About

Modern computational chemistry strives to provide an atomistically detailed dynamical description of fundamental chemical processes. The strategy for reaching this goal generally follows a two-step program. In the first step, electronic structure calculations are used to obtain the force fields that the nuclei are subject to. In the second step, molecular dynamics simulations are used to describe the motion of the nuclei. The first step is always based on quantum mechanics, in light of the pronounced quantum nature of the electrons. However, the second step is most often based on classical mechanics. Indeed, classical molecular dynamics simulations are routinely used nowadays for describing the dynamics of complex chemical systems that involve tens of thousands of atoms. However, there are many important situations where classical mechanics cannot be used for describing the dynamics. Our research targets the most chemically relevant examples include:

(1) Linear and nonlinear vibrational and electronic spectroscopy. The transition frequencies in these cases are often much larger than kT. Furthermore, in the spectral signals can be expressed in terms of optical response functions that lack a well defined classical limit.

(2) Vibrational and electronic relaxation. The quantum nature of the pathways of irradiative intramolecular energy redistribution within molecules and intermolecular energy transfer between molecules is attributed to the large gap between vibrational and electronic energy levels.

(3) Proton and electron transfer reactions. The elementary steps of many complex chemical processes are based on such reactions. Their pronounced quantum nature is attributed to the light mass of protons and electrons, which often gives rise to quantum tunneling and zero-point energy effects.

The challenge involved in simulating the quantum molecular dynamics of such systems has to do with the fact that the computational effort involved in solving the time-dependent Schrödinger equation is exponentially larger than that involved in solving Newton’s equations. As a result, a numerically exact solution of the Schrödinger equation is not feasible for a system that consists of more than a few atoms. The main research thrust of the Geva group is aimed at developing rigorous and accurate mixed quantum-classical, quasi-classical and semiclassical methods that would make it possible to simulate equilibrium and nonequilibrium quantum dynamics of systems that consist of hundreds of atoms and molecules. We put emphasis on applications to experimentally-relevant disordered complex condensed phase systems such as molecular liquids, which serve as hosts for many important chemical processes. We also specialize in modeling and analyzing different types of time resolved electronic and vibrational spectra that are used to probe molecular dynamics in those systems, often in collaboration with experimental groups.

**Research Interests:**

1. Theory and simulation of open quantum system dynamics.

2. Decoherence science.

3. Theory and simulation techniques based on quantum master equations.

4. Quantum and classical rate theory.

5. Theory and simulation of electronic energy and charge transfer dynamics in complex molecular systems (liquid solutions, materials and biosystems).

6. Quantum dynamics of driven dissipative systems.

7. Semiclassical and quasiclassical methods for simulating quantum dynamics and spectra in complex molecular systems.

8. Theory and simulation of nonadiabatic chemical dynamics.

9. Theory and simulation of time-resolved nonlinear and multidimensional optical spectra of complex molecular systems.

10. Quantum science and technology.

**Representative Publications:**

1. R. Dutta et al. "Simulating Chemistry on Bosonic Quantum Devices", J. Chem. Theory. Comput. 20 6426-6441 (2024).

2. A. Schubert, S. Bhandari, E. Geva and B. Dunietz “A computational study of the electronic energy and charge transfer rates and pathways in the tetraphenyldibenzoperiflanthene/fullerene interfacial dyad” *J. Phys. Chem. Lett. ***14** 9569−9583 (2023)

3. N. Lyu, A. Miano, I. Tsioutsios, R. Cortinas, K. Jung, Y. Wang, Z. Hu, E. Geva, S. Kais, V.S. Batista “Mapping Molecular Hamiltonians into Hamiltonians of Modular cQED Processors” *J. Chem. Theory Comput. ***19** 6564−6576 (2023).

4. Y. Wang, E. Mulvihill, Z. Hu, N. Lyu, S. Shivpuje, Y. Liu, M. B. Soley, E. Geva, V. S. Batista and S. Kais “Simulation of open quantum system dynamics based on the generalized quantum master equation on quantum computing devices” *J. Chem. Theory Comput. ***19*** *4851–4862 (2023).

5. M.A.C. Saller, Y. Lai and E. Geva “Cavity-modified Fermi’s golden rule rate constants from cavity-free inputs” *J. Phys. Chem. C* **127** 3154-3164 (2023)

6. N. Lyu, E. Mulvihill, M. Soley, E. Geva and V. Batista “Tensor-Train Thermo-Field Memory Kernels for Generalized Quantum Master Equations” *J. Chem. Theory Comput. ***19** 1111−1129 (2023).

7. E. Mulvihill and E. Geva “Simulating the Dynamics of Electronic Observables via Reduced-Dimensionality Generalized Quantum Master Equations” *J. Chem. Phys. ***156** 044119-17 (2022).

8. J. Tinnin, S. Bhandari, P. Zhang, E. Geva, B. Dunietz, X. Sun and M. Cheung “Correlating Interfacial Charge Transfer Rates with Interfacial Molecular Structure in the Tetraphenyldibenzoperiflanthene/C70 Organic Photovoltaic System” *J. Phys. Chem. Lett. ***13** 763-769 (2022)

9. E. Mulvihill and E. Geva “A Road Map to Various Pathways for Calculating the Memory Kernel of the Generalized Quantum Master Equation” *J. Phys. Chem. B ***125** 34, 9834–9852 (2021).

10. J. Tinnin, H Aksu, Z. Tong, P. Zhang, E. Geva, B. Dunietz, X. Sun and M. Cheung “CTRAMER: An open-source software package for correlating interfacial charge transfer rate constants with donor/acceptor geometries in organic photovoltaic materials”, *J. Chem. Phys. ***154** 214108 (2021).

11. X. Gao and E. Geva “A Nonperturbative Methodology for Simulating Multidimensional Spectra of Multi-excitonic Molecular Systems via Quasiclassical Mapping Hamiltonian Methods”, *J. Chem. Theory Comput.* **16** 6491-6502 (2020).

12. X. Gao, M. A. C. Saller, Y. Liu, A. Kelly, J. O. Richardson and E. Geva “Benchmarking Quasiclassical Mapping Hamiltonian Methods for Simulating Electronically Nonadiabatic Molecular Dynamics” *J. Chem. Theory Comput.* **16** 2883−2895 (2020).

### About

Modern computational chemistry strives to provide an atomistically detailed dynamical description of fundamental chemical processes. The strategy for reaching this goal generally follows a two-step program. In the first step, electronic structure calculations are used to obtain the force fields that the nuclei are subject to. In the second step, molecular dynamics simulations are used to describe the motion of the nuclei. The first step is always based on quantum mechanics, in light of the pronounced quantum nature of the electrons. However, the second step is most often based on classical mechanics. Indeed, classical molecular dynamics simulations are routinely used nowadays for describing the dynamics of complex chemical systems that involve tens of thousands of atoms. However, there are many important situations where classical mechanics cannot be used for describing the dynamics. Our research targets the most chemically relevant examples include:

(1) Linear and nonlinear vibrational and electronic spectroscopy. The transition frequencies in these cases are often much larger than kT. Furthermore, in the spectral signals can be expressed in terms of optical response functions that lack a well defined classical limit.

(2) Vibrational and electronic relaxation. The quantum nature of the pathways of irradiative intramolecular energy redistribution within molecules and intermolecular energy transfer between molecules is attributed to the large gap between vibrational and electronic energy levels.

(3) Proton and electron transfer reactions. The elementary steps of many complex chemical processes are based on such reactions. Their pronounced quantum nature is attributed to the light mass of protons and electrons, which often gives rise to quantum tunneling and zero-point energy effects.

The challenge involved in simulating the quantum molecular dynamics of such systems has to do with the fact that the computational effort involved in solving the time-dependent Schrödinger equation is exponentially larger than that involved in solving Newton’s equations. As a result, a numerically exact solution of the Schrödinger equation is not feasible for a system that consists of more than a few atoms. The main research thrust of the Geva group is aimed at developing rigorous and accurate mixed quantum-classical, quasi-classical and semiclassical methods that would make it possible to simulate equilibrium and nonequilibrium quantum dynamics of systems that consist of hundreds of atoms and molecules. We put emphasis on applications to experimentally-relevant disordered complex condensed phase systems such as molecular liquids, which serve as hosts for many important chemical processes. We also specialize in modeling and analyzing different types of time resolved electronic and vibrational spectra that are used to probe molecular dynamics in those systems, often in collaboration with experimental groups.

**Research Interests:**

1. Theory and simulation of open quantum system dynamics.

2. Decoherence science.

3. Theory and simulation techniques based on quantum master equations.

4. Quantum and classical rate theory.

5. Theory and simulation of electronic energy and charge transfer dynamics in complex molecular systems (liquid solutions, materials and biosystems).

6. Quantum dynamics of driven dissipative systems.

7. Semiclassical and quasiclassical methods for simulating quantum dynamics and spectra in complex molecular systems.

8. Theory and simulation of nonadiabatic chemical dynamics.

9. Theory and simulation of time-resolved nonlinear and multidimensional optical spectra of complex molecular systems.

10. Quantum science and technology.

**Representative Publications:**

1. R. Dutta et al. "Simulating Chemistry on Bosonic Quantum Devices", J. Chem. Theory. Comput. 20 6426-6441 (2024).

2. A. Schubert, S. Bhandari, E. Geva and B. Dunietz “A computational study of the electronic energy and charge transfer rates and pathways in the tetraphenyldibenzoperiflanthene/fullerene interfacial dyad” *J. Phys. Chem. Lett. ***14** 9569−9583 (2023)

3. N. Lyu, A. Miano, I. Tsioutsios, R. Cortinas, K. Jung, Y. Wang, Z. Hu, E. Geva, S. Kais, V.S. Batista “Mapping Molecular Hamiltonians into Hamiltonians of Modular cQED Processors” *J. Chem. Theory Comput. ***19** 6564−6576 (2023).

4. Y. Wang, E. Mulvihill, Z. Hu, N. Lyu, S. Shivpuje, Y. Liu, M. B. Soley, E. Geva, V. S. Batista and S. Kais “Simulation of open quantum system dynamics based on the generalized quantum master equation on quantum computing devices” *J. Chem. Theory Comput. ***19*** *4851–4862 (2023).

5. M.A.C. Saller, Y. Lai and E. Geva “Cavity-modified Fermi’s golden rule rate constants from cavity-free inputs” *J. Phys. Chem. C* **127** 3154-3164 (2023)

6. N. Lyu, E. Mulvihill, M. Soley, E. Geva and V. Batista “Tensor-Train Thermo-Field Memory Kernels for Generalized Quantum Master Equations” *J. Chem. Theory Comput. ***19** 1111−1129 (2023).

7. E. Mulvihill and E. Geva “Simulating the Dynamics of Electronic Observables via Reduced-Dimensionality Generalized Quantum Master Equations” *J. Chem. Phys. ***156** 044119-17 (2022).

8. J. Tinnin, S. Bhandari, P. Zhang, E. Geva, B. Dunietz, X. Sun and M. Cheung “Correlating Interfacial Charge Transfer Rates with Interfacial Molecular Structure in the Tetraphenyldibenzoperiflanthene/C70 Organic Photovoltaic System” *J. Phys. Chem. Lett. ***13** 763-769 (2022)

9. E. Mulvihill and E. Geva “A Road Map to Various Pathways for Calculating the Memory Kernel of the Generalized Quantum Master Equation” *J. Phys. Chem. B ***125** 34, 9834–9852 (2021).

10. J. Tinnin, H Aksu, Z. Tong, P. Zhang, E. Geva, B. Dunietz, X. Sun and M. Cheung “CTRAMER: An open-source software package for correlating interfacial charge transfer rate constants with donor/acceptor geometries in organic photovoltaic materials”, *J. Chem. Phys. ***154** 214108 (2021).

11. X. Gao and E. Geva “A Nonperturbative Methodology for Simulating Multidimensional Spectra of Multi-excitonic Molecular Systems via Quasiclassical Mapping Hamiltonian Methods”, *J. Chem. Theory Comput.* **16** 6491-6502 (2020).

12. X. Gao, M. A. C. Saller, Y. Liu, A. Kelly, J. O. Richardson and E. Geva “Benchmarking Quasiclassical Mapping Hamiltonian Methods for Simulating Electronically Nonadiabatic Molecular Dynamics” *J. Chem. Theory Comput.* **16** 2883−2895 (2020).