F₂ dimer: Improved intermolecular potential energy surface using ab initio calculations

Abstract

A computational study on the intermolecular potential energy of 44 different orientations of F2 dimers is presented. Basis set superposition error (BSSE) corrected potential energy surface is calculated using the supermolecular approach at CCSD(T) and QCISD(T) levels of theory. The interaction energies obtained using the aug‐cc‐pVDZ and aug‐cc‐pVTZ basis sets are extrapolated to the complete basis set limit using the latest extrapolation scheme. The basis set effect is checked and it is found that the extrapolated intermolecular energies provide the best compromise between the accuracy and computational cost. Among 1320 energy points of F2–F2 system covering more relative orientations, the most stable structure of the dimers was obtained with a well depth of −146.62 cm−1 that related to cross configuration, and the most unstable structure is related to linear orientation with a well depth of −52.63 cm−1. The calculated second virial coefficients are in good agreement with experimental data. The latest extrapolation scheme of the complete basis set limit at the CCSD(T) level of theory is used to determine the intermolecular potential energy surface of the F2 dimer. Comparing the results obtained by the latest scheme with those by older schemes show that the new approach provides the best compromise between accuracy and computational cost.

Mg3F7: A superhalogen with potential for new nanomaterials design

“…These hypervalent structures were given the name "superhalogens" by Gutsev and Boldyrev who proposed their existence in the early 1980s and have introduced a simple MX k + 1 formula, where M is the main group or the transition metal atom, X is a halogen atom, and k is the maximal formal valence of the atom M. [4] Up to now, a great number of theoretical and experimental studies have been performed to explore new superhalogen species and find ways to increase their application scope. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] The main aim of investigating novel superhalogen systems is to deliver reliable data and predictions considering the possible use of such compounds as electron acceptors (oxidizing agents). Due to their strong oxidizing capability, superhalogens can be used to access the high oxidation states otherwise unreachable in conventional chemistry.…”