First principle study of CrF n (n = 1–7) nano clusters: An investigation of superhalogen properties

Abstract

Quantum chemical calculations using gradient corrected density functional theory at B3LYP level reveals the unusual properties of a chromium (Cr) atom interacting with fluorine (F) atoms. Up to seven F atoms are bound to a single Cr atom, which results in increase of electron affinities as successive fluorine atoms are attached, reaching a peak value of 7.14 eV for CrF 6 . The large HOMO-LUMO energy gap, both in neutral and anionic form, further provide evidence of their stability. These unusual properties brought about by involvement of inner shell 3d-electrons, which not only allow CrF n (n = 1-7) clusters to belong to the class of superhalogens but also show that its valence can exceed the nominal value of 2.

Ab initio investigations on the stabilities of AuO n q − (q = 0 to 3; n = 1 to 4) species: Superhalogen behavior of AuOn (n ≥ 2) and their interactions with an alkali metal

“…A hybrid form of functional for exchange‐correlation terms, B3LYP in conjunction with a double zeta type basis set, Stuttgart‐Dresden‐Dunning (SDD) for all atoms is used throughout the calculations. The present computational scheme has already been used in some previous studies , and has provided reliable geometries and energetics of superhalogen species. Furthermore, this computational scheme yields the bond lengths of KCl and O 2 as 2.79 and 1.27 Å, respectively and agrees well with the corresponding experimental values of 2.67 and 1.21 Å .…”

“…For instance, the adiabatic EA of AuF 6 has been estimated as 9.5–10.5 eV . Recently, superhalogen properties of many transition metals with different number of F ligands have been reported , . It is quite interesting to observe the case of transition metals with O ligands.…”

A Comprehensive Topological Analysis of a Novel Flavonoid Extracted from Brazilian Cerrado Plants

“…The NBO analysis was performed at the M06-2X/6-311 + G (d,p) (the non-hydrogen atoms were taken from the crystallographic data while the hydrogens atoms were optimized) level of theory. The hyperconjugative interaction energy can be estimated from the second-order perturbation, [27] as described in Equation 2: where hs F j jsi 2 is the Fock matrix element between the i and j NBO orbitals. e * s and e s are the energies of s and s * NBO's and n s is the population of the donor s orbital.…”

Quantum chemical studies on the structural and electronic properties of nickel sulphide and iron sulphide nanoclusters

“…The obtained energy and dipole moment of geometrically optimized clusters are tabulated in Table 1. The HOMO-LUMO gap gives the electronic properties of NiS nanoclusters [22,23]. Usually a low value of gap implies that the electron can easily move from the occupied level to the virtual level.…”