Fundamental Vibrational Frequencies of Pnictogen (Pn) Containing Linear Triatomic Anions: Ocpn ⁻ and Scpn - Where Pn = N, P, as and Sb
Abstract
The fundamental vibrational frequencies of the isolated OCAs (Formula presented.) and SCAs (Formula presented.) ions, as well as their heavier antimony analogues, are reported for the first time. A thorough analysis of basis set convergence of the bond lengths and harmonic vibrational frequencies, as well as the examination of anharmonic corrections, is conducted using the MP2 and CCSD(T) ab initio methods with robust basis sets for the OC (Formula presented.) and SC (Formula presented.) anions moving down the pnictogen series from Pn = N to Sb. Second-order vibrational perturbation theory (VPT2) and vibrational configuration interaction (VCI) theory are used to compute the fundamental vibrational frequencies of each triatomic anion approaching the MP2 and CCSD(T) complete basis set (CBS) limits. While fundamental vibrational frequencies have been reported for OCN (Formula presented.) and SCN (Formula presented.) in the gas phase, only experimental vibrational frequencies of the salts for the heavier pnictogen analogues (P and As) have been reported. Experimental Raman vibrational frequencies for OCAs (Formula presented.) and SCAs (Formula presented.) salts were found to be coincidentally in good agreement with the CCSD(T) VCI frequencies near the CBS limit, differing by at most 13 cm (Formula presented.) from the former and 9 cm (Formula presented.) from the latter. These modest differences are likely due to the presence of counter-ions and other environmental effects in the solid state, and the overall agreement between the salts and gas-phase frequencies is quite similar to that observed for the OCP (Formula presented.) and SCP (Formula presented.) ions.
Recommended Citation
K. R. Barlow and G. S. Tschumper, "Fundamental Vibrational Frequencies of Pnictogen (Pn) Containing Linear Triatomic Anions: Ocpn ⁻ and Scpn - Where Pn = N, P, as and Sb," Molecular Physics, vol. 122, no. 7 thru 8, article no. e2262621, Taylor and Francis Group; Taylor and Francis, Jan 2024.
The definitive version is available at https://doi.org/10.1080/00268976.2023.2262621
Department(s)
Chemistry
Keywords and Phrases
anharmonic fundamental vibrational frequencies; cyanate analogues; Pnictogen-containing anions; second-order vibrational perturbation theory (VPT2); vibrational configuration interaction (VCI) theory
International Standard Serial Number (ISSN)
1362-3028; 0026-8976
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Taylor and Francis Group; Taylor and Francis, All rights reserved.
Publication Date
01 Jan 2024
