RT Journal Article
T1 Equilibrium structures of selenium compounds: The torsionally flexible molecule of selenophenol
A1 Li, Wenquin
A1 Juanes, Marcos
A1 Demaison, Jean
A1 Vogt, Natalja
A1 Fernández Ramos, Antonio
A1 Lesarri, Alberto
A1 Saragi, Rizalina Tama
K1 Selenio
K1 Selenofenol
AB The equilibrium structure of selenophenol has been investigated using rotational spectroscopy and high-level quantum mechanical calculations, offering electronic and structural insight into the scarcely studied selenium compounds. The jet-cooled broadband microwave spectrum was measured in the 2–8 GHz cm-wave region using broadband (chirped-pulse) fast-passage techniques. Additional measurements up to 18 GHz used narrow-band impulse excitation. Spectral signatures were obtained for six isotopic species of selenium (80Se, 78Se, 76Se, 82Se, 77Se, and 74Se), together with different monosubstituted 13C species. The (unsplit) rotational transitions associated with the non-inverting μa-dipole selection rules could be partially reproduced with a semirigid rotor model. However, the internal rotation barrier of the selenol group splits the vibrational ground state into two subtorsional levels, doubling the dipole-inverting μb transitions. The simulation of the double-minimum internal rotation gives a very low barrier height (B3PW91: 42 cm−1), much smaller than for thiophenol (277 cm−1). Amonodimensional Hamiltonian then predicts a huge vibrational separation of 72.2 GHz, justifying the non-observation of μb transitions in our frequency range. The experimental rotational parameters were compared with different MP2 and density functional theory calculations. The equilibrium structure was determined using several high-level ab initio calculations. A final Born–Oppenheimer (rBOe ) structure was obtained at the coupled-cluster CCSD(T)_ae/cc-wCVTZ level of theory, including small corrections for the wCVTZ → wCVQZ basis set enlargement calculated at the MP2 level. The mass-dependent method with predicates was used to produce an alternative r(2)m structure. The comparison between the two methods confirms the high accuracy of the rBOe structure and offers information on other chalcogen-containing molecules
PB AIP Publishing
SN 0021-9606
YR 2023
FD 2023
LK https://hdl.handle.net/10347/38575
UL https://hdl.handle.net/10347/38575
LA eng
NO Li, W., Saragi, R. T., Juanes, M., Demaison, J., Vogt, N., Fernández-Ramos, A., Lesarri, A. (2023). Equilibrium structures of selenium compounds: The torsionally flexible molecule of selenophenol. "The Journal Of Chemical Physics", 159, 024303
NO This work was supported by the Dr. B. Mez-Starck Foundation (Germany). W.L., R.T.S., M.J., and A.L. acknowledge the funding from the European Regional Development Fund (ERDF) and the Ministerio de Ciencia e Innovación (Grant No. PID2021-125015NB-I00) and Junta de Castilla y León (Grant Nos. INFRARED IR2020-1-UVa02 and INFRARED IR2021-UVa13). A.F.-R. thanks the Centro de Supercomputación de Galicia (CESGA) for the use of their computational facilities, Consellería de Cultura, Educación e Ordenación Universitaria (Centro singular de investigación de Galicia acreditación 2019–2022, ED431G 2019/03, and Grupo de Referencia Competitiva ED431C 2021/40), the European Regional Development Fund (ERDF), and the Ministerio de Ciencia e Innovación through Grant No. PID2019-107307RB-I00. W.L. thanks the China Scholarship Council (CSC) for a scholarship
DS Minerva
RD 24 abr 2026