02823nas a2200313 4500008004100000022001400041245009900055210006900154260000800223300001600231490000700247520186600254653001702120653001302137653001802150653001402168653003202182653001302214653001602227653001202243653001302255653001102268100002202279700002302301700001902324700002102343700001502364856013002379 2017 eng d a1463-907600aNature of selenium hydrogen bonding: gas phase spectroscopy and quantum chemistry calculations0 aNature of selenium hydrogen bonding gas phase spectroscopy and q cSEP a24179-241870 v193 a

Subsequent to the recent re-definition of hydrogen bonding by the IUPAC committee, there has been a growing search for finding the presence of this ever interesting non-covalent interaction between a hydrogen atom in an X-H group and any other atom in the periodic table. In recent gas phase experiments, it has been observed that hydrogen bonding interactions involving S and Se are of similar strength to those with an O atom. However, there is no clear explanation for the unusual strength of this interaction in the case of hydrogen bond acceptors which are not conventional electronegative atoms. In this work, we have explored the nature of Se hydrogen bonding by studying indole...dimethyl selenide (indmse) and phenol...dimethyl selenide (phdmse) complexes using gas phase IR spectroscopy and quantum chemistry calculations. We have found through various energy decomposition analysis (EDA) methods and natural bond orbital (NBO) calculations that, along with electrostatics and polarization, charge transfer interactions are important to understand Se/S hydrogen bonding and there is a delicate balance between the various interactions that plays the crucial role rather than a single component of the interaction energy. An in-depth understanding of this type of non-covalent interaction has immense significance in biology as amino acids containing S and Se are widely present in proteins and hence hydrogen bonding interactions involving S and Se atoms contribute to the folding of proteins.

 

10aCenter-Dot-O10aClusters10aCo-Ordination10aComplexes10aintermolecular interactions10aProteins10aReplacement10aspectra10aStrength10aSulfur1 aMishra, Kamal, K.1 aSingh, Santosh, K.1 aGhosh, Paulami1 aGhosh, Debashree1 aDas, Aloke uhttps://library.ncl.res.in/content/nature-selenium-hydrogen-bonding-gas-phase-spectroscopy-and-quantum-chemistry-calculations