Dr. Jorge A. Morales
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Title: |
Associate Professor |
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Education: |
Ph.D., University of Florida, 1997; Postdoctoral Study, University of Illinois, 1998-2001 |
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Research Area: |
Theoretical Chemistry and Chemical Physics |
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Office: |
Chemistry 039 |
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Principal Research Interests
- Novel Coherent-States Theory for Nuclear and Electronic Degrees of Freedom
- Direct, Time-Dependent, Coherent-States Molecular Dynamics
- Hybrid Quantum/Classical Methods
- Quantum Chemistry Studies of Molecular Clusters
The main focus of our present research efforts is the direct, time-dependent simulation of chemical reactions. In that approach, a reaction is simulated in the same way the process evolves in “real life” (i.e. by evaluating instantaneously the reaction evolution and its acting molecular forces “on the fly”, without the cumbersome time-independent predetermination of potential energy surfaces). In the main, quantum mechanics is the theoretical framework of our simulations. However, even with the current computer technology, full quantum-mechanics descriptions of large chemical systems remain impractical and recurrences to more feasible classical-mechanics treatments are inevitable. Therefore, we advocate a generalized quantum/classical (Q/C) approach to ab initio molecular mechanics where molecular degrees of freedom and/or molecular regions are distributed into quantum and classical treatments. Degrees of freedom less critical for quantum effects (e.g. nuclear translational, rotational and vibrational motions under some circumstances) and/or a peripheral molecular region not housing quantum processes can be treated via classical mechanics with added quantum corrections. Conversely, the central region containing quantum phenomena (e.g. tunneling) must be described quantum-mechanically.
Toward such a goal, we are developing a novel Q/C methodology that permits making transitions from quantum to classical treatments in a gradual and continuous way; we attain such flexibility by exploiting the properties of coherent states (CS). Broadly speaking, CS are sets of quantum states that permit expressing quantum dynamical equations in a classic-like format in terms of generalized positions and momenta. Some CS are also quasi-classical if their generalized positions and momenta obey classical mechanics. A CS-formulated dynamics is still quantum but in a classic-like format as close to classical mechanics as possible; furthermore, if a quasi-classical CS is employed for a molecular region and/or a degree of freedom then a classical dynamics with a quantum state is obtained and a Q/C partition is created.
A highlight of creativity in our CS efforts is the original formulation of novel types of CS to implement such a CS dynamics. Whereas nearly all previous chemical research on CS has mostly dealt with the celebrated Glauber CS to describe nuclear motions, we are endeavoring for the creation and/or use of novel types of CS for all types of particles (nuclei and electrons) and for all types of dynamics (translational, rotational, vibrational, electronic). Our CS dynamics is being implemented into the program CSDYN (= CS Dynamics). CSDYN is a complex code that contains original CS capabilities, novel CS/density functional theory routines and libraries, and compute grid implementations for Microsoft Windows® and Red Hat Linux® operating systems inter alia.
Our current projects include:
- A CS/Density Functional Theory Approach to Ab Initio Molecular Dynamics
- A Valence-Bond/CS Formulation of a Generalized Charge Equilibration Models
- A CS Transition Probability Amplitude Procedure to Evaluate Reaction Properties
- The Compute Grid Implementation of Our CS Dynamics
- Simulations of Aqueous Metal-Ion Clusters
- Computational Studies on Pure Non-Metal and Metal/Non-Metal Clusters
Representative Publications
- "Dynamics of H+ + CO at ELab = 30 eV", C. Stopera, B. Maiti, T. V. Grimes, P. M. McLaurin and J. A. Morales, Accepted for Publication in the Journal of Chemical Physics, 136, 054304 (2012)
- "Dynamics of H+ + N2 at ELab = 30 eV", C. Stopera, B. Maiti, T. V. Grimes, P. M. McLaurin and J. A. Morales, Journal of Chemical Physics, 134, 224308 (2011)
- "Some Coherent-States Aspects of the Electron Nuclear Dynamics Theory: Past and Present", J. A. Morales, Molecular Physics, 108, 3199-3211 (2010)
- "Time-Dependent Density-Functional Theory Method in The Electron Nuclear Dynamics Framework", S. A. Perera, P. M. McLaurin, T. V. Grimes, and J. A. Morales, Chemical Physics Letters, 496, 188-195 (2010)
- "Valence-Bond/Coherent-States Approach to The Charge Equilibration Model I. Valence-Bond Models for Diatomic Molecules", J. A. Morales, Journal of Physical Chemistry A, 113, 6004-6015 (2009)
- "A Theoretical Investigation on Fullerene-like Phosphorus Clusters", J. G. Han and J. A. Morales, Chemical Physics Letters, 396/1-3, 27 (2004)
- "The Onset of Dissociation in The Aqueous LiOH Clusters: A Solvation Study with the Effective Fragment Potential Model and Quantum Mechanics Methods", A. Yoshikawa and J. A. Morales, Journal of Molecular Structure (Theochem), 681, 27 (2004)
- "New Approach to Reactive Potentials with Fluctuating Charges: Quadratic Valence-Bond Model", J. A. Morales and T. J. Martinez, Journal of Physical Chemistry A, 108, 3076 (2004)
- "On The Rotational Coherent State in Molecular Quantum Dynamics", J. A. Morales, E. Deumens and Y. Öhrn, Journal of Mathematical Physics, 40(2), 766 (1999)
- "Electron Nuclear Dynamics of H+ + H2 Collisions at ELab = 30 eV", J. A. Morales, A. Diz, E. Deumens and Y. Öhrn, Journal of Chemical Physics, 103, 9968 (1995)
- "Perturbation Theory without Functions for the Zeeman Effect in Hydrogen", F. M. Fernandez and J. A. Morales, Physics Review A, 46, 318 (1992)
