tailieunhanh - Unveiling geometric and electronic structures of NbSi4 −/0 clusters and electron detachments of the anionic cluster: A quantum chemical investigation

This article presents computational insights into the geometric and electronic structures of NbSi4 −/0 clusters using density functional theory and the CASSCF/CASPT2 method. The anionic and neutral ground states are identified as the 1A′ and 2A′ states, respectively, within a trigonal bipyramidal isomer where the Nb atom occupies the equatorial position. The adiabatic detachment energy for the transition from the anionic ground state 1A′ to the neutral ground state 2A′ is estimated to be eV. | Received 17 October 2023 Revised 4 January 2024 Accepted 13 January 2024 DOI RESEARCH ARTICLE Unveiling geometric and electronic structures of NbSi4 0 clusters and electron detachments of the anionic cluster A quantum chemical investigation Van Tan Tran Theoretical and Physical Chemistry Division Dong Thap University Dong Thap Vietnam Abstract This article presents computational insights into the geometric and elec- Correspondence tronic structures of NbSi4 0 clusters using density functional theory and the Van Tan Tran Theoretical and Physical Chemistry Division Dong Thap University 783-Pham Huu CASSCF CASPT2 method. The anionic and neutral ground states are identified as Lau Ward 6 Cao Lanh City Dong Thap 81000 the 1 A and 2 A states respectively within a trigonal bipyramidal isomer where Vietnam. the Nb atom occupies the equatorial position. The adiabatic detachment energy Email tvtan@ for the transition from the anionic ground state 1 A to the neutral ground state 2 A is estimated to be eV. Additionally an evaluation of the vertical detachment energies for transitions to the neutral states 12 A 12 A 22 A 22 A 32 A 32 A and 42 A yields respective values of and eV. These computed electron detachment energies successfully account for all five bands observed in the photoelectron spectrum of the anionic cluster. Furthermore the Franck Condon factor simulations reveal extensive vibrational progressions asso- ciated with the transition to the neutral ground state 12 A manifesting as an unresolved broad band at eV in the spectrum. KEYWORDS CASPT2 detachment energy density functional theory electronic state Franck Condon factor geometric structure 1 INTRODUCTION NbSi4 cluster exhibits five features with vertical detach- ment energies VDEs of and eV. The structures and properties of many transition Niobium The adiabatic detachment energy ADE of the first band silicide