Indirect Nuclear 77Se?77Se Spin?Spin Coupling Constants. Application of Density Functional Theory (DFT) Calculations

Abstract

Calculations of the isotropic indirect nuclear spin-spin coupling constants n J( 77 Se, 77 Se) (n = 1,2,3) have been carried out at the B3LYP/6-311+G(d,p) level of theory. The compounds considered were non-cyclic and cyclic diselanes 1, boryl-substituted diselanes 2, dichlorodiselane 4, selenium Se 8 , Se 6 , Se 5 and various mixed selenium sulfides 3, and the bis(ethylene)tetraselenafulvalene (TSeF) 5. In comparison with experiment, both magnitude and sign, if available, were reproduced. The Coupled Perturbed DFT method gave the total coupling constant and the contributions arising from the Fermi contact term (FC), the spin-dipole (SD) and the spin.orbital terms (PSO and DSO). FC contributions play a minor role in most cases when compared with the non-contact terms.SD and PSO.

Structural, energetic and response electric properties of cyclic selenium clusters: an ab initio and density functional theory study

“…levels [36,49], for Se 5 at the B3LYP/ 6-311?G(d,p) and B3LYP/DZP?? levels [40,49] and for Se 6 and Se 8 at the PBE0/cc-pVTZ and PBE0/6-311G(d) levels [41]. In addition, for the Se 2 , Se 6 and Se 8 clusters, the present calculated gas-phase geometries are in reasonable agreement with the experimental ones determined in the solid (within 0.03-0.04 Å ) [16][17][18].…”

“…Selenium clusters adsorbed into zeolite channels are bonded to each other and to the host matrices by van der Waals forces controlled by the polarizabilities of the clusters [21,35]. On the theoretical side, geometries, relative stabilities, binding energies of selenium clusters are available from the literature [12,[36][37][38][39][40][41][42][43][44][45][46][47][48][49].…”

Solid-state selenium-77 NMR

“…Numerous investigations of calculated selenium magnetic shielding and/or chemical shift tensors have been reported [72][73][74][75][76][77][78][79][80]. Additionally, recent theoretical computations of indirect spin-spin coupling constants involving selenium have appeared in the literature [81][82][83]. The interested reader is encouraged to pursue these references for a more detailed description of the intricacies of calculating 77 Se NMR parameters.…”

Quantum chemical calculations of77Se and125Te nuclear magnetic resonance spectral parameters and their structural applications

“…The nonrelativistic IGLO‐ and GIAO‐DFT studies of 77 Se NMR chemical shifts were reported in a wide series of papers. [ 146–159 ]…”

“…The nonrelativistic IGLO-and GIAO-DFT studies of 77 Se NMR chemical shifts were reported in a wide series of papers. [146][147][148][149][150][151][152][153][154][155][156][157][158][159] The example of recent accurate nonrelativistic DFT study of the 77 Se chemical shifts can be found in previous works [160,161] intended to investigate the conformational preferences of selenocysteine and L-selenocystine using the 77 Se NMR spectroscopy. Their geometry and chemical environment in selenoproteins are known to shape their ability to act as a nucleophile and thus impact their reactivity.…”