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Title: A new Gaussian MCTDH program: Implementation and validation on the levels of the water and glycine molecules

We report the main features of a new general implementation of the Gaussian Multi-Configuration Time-Dependent Hartree model. The code allows effective computations of time-dependent phenomena, including calculation of vibronic spectra (in one or more electronic states), relative state populations, etc. Moreover, by expressing the Dirac-Frenkel variational principle in terms of an effective Hamiltonian, we are able to provide a new reliable estimate of the representation error. After validating the code on simple one-dimensional systems, we analyze the harmonic and anharmonic vibrational spectra of water and glycine showing that reliable and converged energy levels can be obtained with reasonable computing resources. The data obtained on water and glycine are compared with results of previous calculations using the vibrational second-order perturbation theory method. Additional features and perspectives are also shortly discussed.
Authors:
;  [1]
  1. Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa (Italy)
Publication Date:
OSTI Identifier:
22311382
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 24; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ENERGY LEVELS; GLYCINE; HAMILTONIANS; MOLECULES; PERTURBATION THEORY; SPECTRA; TIME DEPENDENCE; VALIDATION; VARIATIONAL METHODS; WATER