Franck-Condon simulation of the photoelectron spectrum of AsCl2and the photodetachment spectrum of AsCl-2- Employing UCCSD(T)-F12a potential energy functions: IE and EA of AsCl2

Kam Wah Mok, Edmond P.F. Lee, Foo Tim Chau, John M. Dyke

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3 Citations (Scopus)


The currently most reliable theoretical estimates of the adiabatic ionization energies (AIE0) from the X̄2B1state of AsCl2to the X̄1A1and Ā£3B1states of AsCl+2, and the electron affinity (EA0) of AsCl2, including δZPE corrections, are calculated as 8.687(11), 11.320(23), and 1.845(12) eV, respectively (estimated uncertainties based on basis-set effects at the RCCSD(T) level). State-of-the-art ab initio calculations, which include RCCSD(T), CASSCF/MRCI, and explicitly correlated RHF/UCCSD(T)-F12x (x = a or b) calculations with basis sets of up to quintuple-zeta quality, have been carried out on the X̄2B1state of AsCl2, the X̄1A1, Ā£3B1, and Ā1B1states of AsCl+2, and the X̄1A1state of AsCl-2. Relativistic, core correlation and complete basis-set (CBS) effects have been considered. In addition, computed UCCSD(T)-F12a potential energy functions of relevant electronic states of AsCl2, AsCl+2, and AsCl-2were used to calculate Franck-Condon factors, which were then used to simulate the valence photoelectron spectrum of AsCl2and the photodetachment spectrum of AsCl-2, both yet to be recorded. Lastly, we have also computed the AIE and EA values for NCl2, PCl2, and AsCl2at the G4 level and for SbCl2at the RCCSD(T)/CBS level. The trends in the AIE and EA values of the group V pnictogen dichlorides, PnCl2, where Pn = N, P, As, and Sb, were examined. The AIE and EA of PCl2were found to be smaller than those of AsCl2, contrary to the order expected from the IE values of P and As. J Comput Chem, 2011
Original languageEnglish
Pages (from-to)1648-1660
Number of pages13
JournalJournal of Computational Chemistry
Issue number8
Publication statusPublished - 1 Jun 2011


  • ab initio calculations
  • AIE and EA values of Pnictogen dichlorides
  • Franck-Condon factors
  • IE and EA of AsCl 2
  • photodetachment of AsCl -2 -
  • photoelectron spectrum of AsCl 2

ASJC Scopus subject areas

  • Chemistry(all)
  • Computational Mathematics

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