Faculty

Michael Herman

Professor
Ph.D., 1980, Chicago

Office: 5010 Percival Stern Building
Email: mherman@tulane.edu
Phone: (504) 862-3582

Discipline

Physical Chemistry

Areas of current interest

My research program focuses on two main topics in theoretical chemistry. The first research area involves the development and testing of semiclassical approximations for the quantum evolution of complex systems. Semiclassical methods, which utilize information from classical trajectories to obtain approximate quantum mechanical energies, wavefunctions, transition probabilities, etc., provide computationally very useful procedures for calculations involving the motion of atomic and molecular systems.

The second area investigates the manner in which solvents influence the vibrational frequencies and population relaxation in liquids and dense gases. These interactions are important because, for instance, the equilibration of vibrational populations plays a significant role in determining the response of condensed phase systems to external perturbations.

Selected Publications

MF Herman, F Ding, On the importance of the classically forbidden region in calculations of the relaxation rate for high-frequency vibrations: A model calculation, Journal of Physical Chemistry A, 111 (41), pp. 10186-10190 (2007).

Y Wu, MF Herman, On the properties of a primitive semiclassical surface hopping propagator for nonadiabatic quantum dynamics, Journal of Chemical Physics, 127 (4), art. no. 044109 (2007).

MF Herman, A Sergeev, Using an r -dependent Gaussian width in calculations of the globally uniform semiclassical wave function, Journal of Chemical Physics, 126 (3), art. no. 034104 (2007).

Y Wu, MF Herman, A justification for a nonadiabatic surface hopping Herman-Kluk semiclassical initial value representation of the time evolution operator, Journal of Chemical Physics, 125 (15), art. no. 154116, (2006).

A Sergeev, MF Herman, An analysis of the accuracy of an initial value representation surface hopping wave function in the interaction and asymptotic regions, Journal of Chemical Physics, 125 (2), art. no. 024107, (2006).

MF Herman, Toward an accurate and efficient semiclassical surface hopping procedure for nonadiabatic problems, Journal of Physical Chemistry A, 109 (41), pp. 9196-9205 (2005).

Y Wu, MF Herman, Nonadiabatic surface hopping Herman-Kluk semiclassical initial value representation method revisited: Applications to Tully's three model systems, Journal of Chemical Physics, 123 (14), art. no. 144106, pp. 1-11 (2005).

MF Herman, MP Moody, Numerical study of the accuracy and efficiency of various approaches for Monte Carlo surface hopping calculations, Journal of Chemical Physics, 122 (9), pp. 94104 (2005).

Y Wu, MF Herman, VS Batista, Matching-pursuitsplit-operator Fourier-transform simulations of nonadiabatic quantum dynamics, Journal of Chemical Physics, 122 (11), pp. 114114 (2005).

MF Herman, O El Akramine, MP Moody, M.P., Globally uniform semiclassical surface-hopping wave function for nonadiabatic scattering,Journal of Chemical Physics, 120 (16), pp. 7383-7390 (2004).

MH Herman, Q El Akramine, and MP Moody, Globally Uniform Semiclassical Surface-Hopping Wave Function for Nonadiabatic Scattering, J. Chem. Phys., 120, 7383-7390 (2004).

MP Moody, F. Ding and MH Herman, Phase Corrected Higher-Order Expression for Surface Hopping Transition Amplitudes in Nonadiabatic Scattering Problems, J. Chem. Phy 119, 11048-11057 (2003).

F Grossman and MF Herman, Comment on Semiclassical Approximations in Phase Space with Coherent States, J. Phys. A. 35, 9489 (2002).

MF Herman, Comparison of Semiclassical Methods for Time-Dependent Density Evolution for a Two State Model Problem, (Elsevier) Chem. Phys. 273, 175-189 (2001).

MF Herman, A Length Scale Dependent Model for Stress Relaxation in Polymer Melts, Macromolecules, 34, 4580 (2001).

G. Yang and MF Herman, Semiclassical Surface Hopping H-K Propagator: Application to Two Dimensional, Two Surface Problems, J. Phys. Chem. B, 105, 6562 (2001).

Publications: 2000 to Present

“Classical Mechanics and the Spreading of Localized Wavepackets in Condensed Phase Molecular Systems”, M. F. Herman and D. F. Coker, J. Chem. Phys. 111, 1801 (1999).

“Choosing a Good Representation of the Quantum Wavefunction for Semiclassical Surface Hopping Calculations”, M. F. Herman, J. Chem. Phys. 111, 10427 (1999).

“Recent Nuclear Magnetic Resonance Experiments on Polymer Melts: Comments”, M. F. Herman, J. Chem. Phys. 112, 3040 (2000).

“Using Force Field Simulations for the Evaluation of the Monomer Parameters for the Calculation of Diffusion Constants for Long Chain Polymer Melts”, B. V. Panajotova and M. F. Herman, Macromolecules 33, 3932 (2000).

“Semiclassical Surface Hopping Methods for Nonadiabatic Transitions in Condensed Phases”, in: “Theoretical Methods in Condensed Phase Chemistry”, ed. S. Schwartz, Kuwer, Dordrecht, Netherlands, (2000).

“Semiclassical Surface Hopping H-K Propagator: Application to Two Dimensional, Two Surface Problems”, G. Yang and M. F. Herman, J. Phys. Chem. B 105, 6562 (2001).

“A Length Scale Dependent Model for Stress Relaxation in Polymer Melts”, M. F. Herman, Macromolecules 34, 4580 (2001).

“Comparison of Semiclassical Methods for Time Dependent Density Evolution for a Two State Model Problem”, M. F. Herman, Chem. Phys. 273, 175 (2001).

“Comment on ‘Semiclassical Approximations in Phase Space with Coherent States’”, F. Grossmann and M. F. Herman, J. Phys. A. 35, 9489 (2002).

“Phase Corrected Higher-Order Expression for Surface Hopping Transition Amplitudes in Nonadiabatic Scattering Problems”, M. P. Moody, F. Ding, and M. F. Herman, J. Chem. Phys. 119, 11048 (2003).

“Gobally Uniform Semiclassical Surface-Hopping Wave Function for Nonadiabatic Scattering”, M. F. Herman, O. El Akramine, and M. P. Moody, J. Chem. Phys. 120, 7383 (2004).

“Numerical Study of the Accuracy and Efficiency of Various Approaches for Monte Carlo Surface Hopping Calculations”, M. F. Herman and M. P. Moody, J. Chem. Phys.122, 94104 (2005).

“Matching-pursuit/split-operator Fourier-transform simulations of nonadiabatic quantum dynamics”, Y. Wu, M. F. Herman, and V. S. Batista, J. Chem. Phys. 122, 114114 (2005).

“Nonadiabatic Surface Hopping Herman-Kluk Semiclassical Initial Value Representation Method Revisited: Applications to Tully’s Three Model Systems”, Y. Wu and M. F. Herman, J. Chem. Phys. 123, 144106 (2005).

“Toward an Accurate and Efficient Semiclassical Surface Hopping Procedure for Nonadiabatic Problems”, M. F. Herman, J. Phys. Chem. A 109, 9196 (2005).

“An Analysis of the Accuracy of the Globally Uniform Surface Hopping Wave Function in the Interaction and Asymptotic Regions”, A. Sergeev and M. F. Herman, J. Chem. Phys. 125, 024107 (2006).

“A Justification for a Nonadiabatic Surface Hopping Herman-Kluk Semiclassical Initial Value Representation of the Time Evolution Operator”, Y. Wu and M. F. Herman, J. Chem. Phys. 125, 154116 (2006).

“Using an r-Dependent Gaussian Width in Calculations of the Globally Uniform Semiclassical Wave Function”, M. F. Herman and A. Sergeev, J. Chem. Phys. 126, 034104 (2007).

“On the Properties of a Primitive Semiclassical Surface Hopping Propagator for Nonadiabatic Quantum Dynamics”, Y. Wu and M. F. Herman, J. Chem. Phys. 127, 044109 (2007).

“On the Importance of the Classically Forbidden Region in the Calculations of the Relaxation Rate for High Frequency Vibrations: A Model Calculation”, M. F. Herman and F. Ding, J. Phys. Chem. A 111, 10186 (2007).

“An Analysis Through Order ℏ2 of a Surface Hopping Expansion of the Nonadiabatic Wave Function”, M. F. Herman and Y. Wu, J. Chem. Phys. 128, 114105 (2008).

“Higher Order Phase Corrected Transition Amplitudes for Time Dependent Semiclassical Surface Hopping Calculations”, M. F. Herman, Chem. Phys. 351, 51 (2008).

“Semiclassical Nonadiabatic Surface Hopping Wave Function Expansion at Low Energies: Hops in the Forbidden Region”, M. F. Herman, J. Phys. Chem. B 112, 15966 (2008).

“Numerical Studies Concerning the Efficiency of Various Techniques in Time-Independent Surface Hopping Calculations”, Xun Huang and M. F. Herman, Chem. Phys. 353, 138 (2008).

“A Semiclassical Model for the Calculation of Nonadiabatic Transition Probabilities for Classically Forbidden Transitions”, Phuong-Thanh Dang and Michael F. Herman, J. Chem. Phys. 130, 054107 (2009).

“A Singularity Free Surface Hopping Expansion for the Multistate Wave Function”, M. F. Herman, J. Chem. Phys. 131, 214108 (2009).

“Using Semiclassical Surface Hopping for Coupled Partial Wave Calculations on Systems with Non-Spherically Symmetric Potentials”, M. F. Herman, Chem. Phys. 373, 274-282 (2010).