Structures of RgFn (Rg = Xe, Rn, and Element 118. n = 2, 4.) Calculated by Two-component Spin−Orbit Methods. A Spin−Orbit Induced Isomer of (118)F4

1999/02/01 by Young‐Kyu Han, Yoon Sup Lee · 6 citations
Chemistry · Physics and Astronomy · Mathematics · #Inorganic Fluorides and Related Compounds #Advanced Chemical Physics Studies #Atomic and Molecular Physics #Spin–orbit interaction #Ab initio #Orbit (dynamics) #Atomic physics #Degenerate energy levels #Physics #Spin (aerodynamics) #Scalar (mathematics) #Relativistic quantum chemistry #Geometry #Condensed matter physics #Quantum mechanics #Mathematics #Thermodynamics

paper · doi:10.1021/jp983665k

openalex publication_date 1999/02/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/26

Abstract

Ab initio calculations of RgF n (Rg = Xe, Rn, and Element 118; n = 2, 4) were performed using relativistic effective core potentials and two-component HF, MP2, CCSD, and CCSD(T) methods. Geometries were optimized at the HF level with and without effective spin−orbit operators. The D 4 h structures of all tetrafluorides and the linear difluorides are local minima with and without spin−orbit interactions. Spin−orbit contributions makes the T d form of (118)F 4 another local minimum with the energy comparable to that of the D 4 h one. The spin−orbit interactions stabilize the (118) fluorides by a significant margin (∼2.0 eV) and the Rn fluorides by 40−60% (0.2∼ 0.4 eV) of the stabilization energy obtained at the corresponding scalar relativistic level. For (118)F 4, the vibrational frequency of the B 2u mode of the D 4 h form decreases from 143 to 20 cm -1 upon inclusion of the spin−orbit interactions, and a doubly degenerate mode of the T d structure, which is stable only with the inclusion of spin−orbit interactions, has the frequency of 34 cm -1, indicating that the (118)F 4 molecule is very flexible due to spin−orbit effects.

Citations

• Ab initiopseudopotentials for Hg to Rn
• Relativistic effects on the bonding of heavy and superheavy hydrogen halides
• General atomic and molecular electronic structure system
• Spin−Orbit Effects, VSEPR Theory, and the Electronic Structures of Heavy and Superheavy Group IVA Hydrides and Group VIIIA Tetrafluorides. A Partial Role Reversal for Elements 114 and 118
• The chemistry of the superheavy elements. II. The stability of high oxidation states in group 11 elements: Relativistic coupled cluster calculations for the di-, tetra- and hexafluoro metallates of Cu, Ag, Au, and element 111

Cited by

• Gradients for two-component quasirelativistic methods. Application to dihalogenides of element 116
• Spin–orbit effects on the transactinide p-block element monohydrides MH (M=element 113–118)
• Spin−Orbit and Relativistic Effects on Structures and Stabilities of Group 17 Fluorides EF3 (E = I, At, and Element 117): Relativity Induced Stability for the D3h Structure of (117)F3
• Electronic Structure and Chemistry of the Heaviest Elements
• Molecular Hexafluorides
• Oganesson [wikipedia]