Precise Semi-experimental Equilibrium Structure Of Thiazole (c₃h₃ns)

Esselman, Brian J.

Permalink

https://hdl.handle.net/2142/111529 Copy

Description

Title

Precise Semi-experimental Equilibrium Structure Of Thiazole (c₃h₃ns)

Author(s)

Esselman, Brian J.

Contributor(s)

• McMahon, Robert J.
• Woods, R. Claude
• Stanton, John F.
• Zdanovskaia, Maria

Issue Date

2021-06-25

Keyword(s)

Structure determination

Abstract

Thiazole (C$_{3}$H$_{3}$NS, C$_{s}$, $\mu$$_{a}$ = 1.286 D, $\mu$$_{b}$ = 0.966 D) is a five-membered aromatic heterocycle containing a 1,3-substituted sulfur and nitrogen. We analyzed the rotational spectra of thiazole and twenty-one of its isotopologues from 130 – 360 GHz. Heavy atom $^{13}$C, $^{34}$S, $^{33}$S, and $^{15}$N isotopologues were observable in the rotational spectrum of the normal isotopologue at their natural abundance. Two syntheses were performed to generate a variety of deuterium-substituted isotopologues, resulting in multiple isotopic substitutions of each atom in the molecule. The resultant determinable rotational constants were computationally corrected for vibration-rotation interactions and electron mass with CCSD(T) calculations and 22 total isotopologues were least-squares fit to afford the semi-experimental equilibrium structure (r$_{e}$$^{SE}$). Theoretical structures were computed at several levels of theory up to CCSD(T)/cc-pCV5Z. The quintuple zeta structure was further refined to account for extrapolation to the complete basis set limit, residual electron correlation beyond CCSD(T), relativistic effects, and the diagonal Born-Oppenheimer correction. The resultant r$_{e}$$^{SE}$ structure and best theoretical structure are compared.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Permalink

http://hdl.handle.net/2142/111529

DOI

10.15278/isms.2021.FK05

Owning Collections