George S. Fanourgakis

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We report the first harmonic vibrational spectra for each of the lowest lying isomers within the four major families of minima of (H2O)20, namely, the dodecahedron, fused cubes, face-sharing pentagonal prisms, and edge-sharing pentagonal prisms. These were obtained at the second-order Moller-Plesset perturbation level of theory (MP2) with the augmented(More)
The total photofragmentation cross sections of size selected Sr ϩ Ar n ,nϭ2 – 8, clusters have been recorded in a time of flight ͑TOF͒ mass spectrometer. In the energy range of 21 000–27 000 cm Ϫ1 three absorption bands are observed that are attributed to transitions from the ground to the three excited states that correlate to the 5p orbitals of strontium.(More)
The existence of a transitional size regime where preferential stabilization alternates between "all-surface" (all atoms on the surface of a cluster) and "internally solvated" (one water molecule at the center of the cluster, fully solvated) configurations with the addition or the removal of a single water molecule, predicted earlier with the flexible,(More)
We report estimates of complete basis set (CBS) limits at the second-order Møller-Plesset perturbation level of theory (MP2) for the binding energies of the lowest-lying isomers within each of the four major families of minima of (H(2)O)(20). These were obtained by performing MP2 calculations with the family of correlation-consistent basis sets up to(More)
The ring polymer molecular dynamics (RPMD) and partially adiabatic centroid molecular dynamics (PA-CMD) methods are compared and contrasted in an application to the infrared absorption spectrum of a recently parametrized flexible, polarizable, Thole-type potential energy model for liquid water. Both methods predict very similar spectra in the low-frequency(More)
A quantum simulation of an imaginary time path integral typically requires around n times more computational effort than the corresponding classical simulation, where n is the number of ring polymer beads (or imaginary time slices) used in the calculation. It is however possible to improve on this estimate by decomposing the potential into a sum of slowly(More)
We present a new parametrization of the flexible, polarizable Thole-type model for water [J. Chem. Phys. 116, 5115 (2002); J. Phys. Chem. A 110, 4100 (2006)], with emphasis in describing the vibrational spectra of both water clusters and liquid water. The new model is able to produce results of similar quality with the previous versions for the structures(More)
We present a revision of the flexible, polarizable, Thole-type interaction potential for water [J. Chem. Phys.2002, 116, 5115], which allows for condensed-phase simulations. The revised version (TTM2.1-F) of the potential correctly describes the individual water molecular dipole moment and alleviates problems arising at short intermolecular separations that(More)
We report the results of molecular dynamics simulations, which indicate that, by carefully splitting the electrostatic interactions in short- and long-range contributions and employing the charge-neutralization method of Wolf, accurate predictions of various properties of liquid water and aqueous solutions can be achieved without the need for the Ewald(More)
We report converged quantum statistical mechanical simulations of liquid water with the Thole-type Model (version 2.1), Flexible, polarizable (TTM2.1-F) interaction potential for water. Simulations of total length of 600 ps with a 0.05 fs time step for a periodic unit cell of 256 molecules with up to 32 replicas per atom suggest that the quantum effects(More)