Vibrational energies of PH3 calculated variationally at the complete basis set limit

The potential energy surface for the electronic ground state of PH3 was calculated at the CCSD(T) level using aug-cc-pV(Q+d)Z and aug-cc-pVQZ basis sets for P and H, respectively, with scalar relativistic corrections included. A parametrized function was fitted through these ab initio points, and on...

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Detalles Bibliográficos
Autores: Ovsyannikov, Roman I., Thiel, Walter, Yurchenko, Sergei N., Carvajal Zaera, Miguel, Jensen, Per
Tipo de recurso: artículo
Fecha de publicación:2008
País:España
Institución:Universidad de Huelva (UHU)
Repositorio:Arias Montano. Repositorio Institucional de la Universidad de Huelva
Idioma:inglés
OAI Identifier:oai:ariasmontano.uhu.es:10272/5417
Acceso en línea:http://hdl.handle.net/10272/5417
Access Level:acceso abierto
Palabra clave:Química cuántica
Chemistry, physical &amp
theoretical
Potential energy surfaces
Basis sets (Quantum mechanics)
Excited state chemistry
Quantum chemistry
Descripción
Sumario:The potential energy surface for the electronic ground state of PH3 was calculated at the CCSD(T) level using aug-cc-pV(Q+d)Z and aug-cc-pVQZ basis sets for P and H, respectively, with scalar relativistic corrections included. A parametrized function was fitted through these ab initio points, and one parameter of this function was empirically adjusted. This analytical PES was employed in variational calculations of vibrational energies with the newly developed program TROVE. The convergence of the calculated vibrational energies with increasing vibrational basis set size was improved by means of an extrapolation scheme analogous to the complete basis set limit schemes used in ab initio electronic structure calculations. The resulting theoretical energy values are in excellent agreement with the available experimentally derived values.