0438384 - ÚOCHB 2015 RIV GB eng J - Journal Article
Deepa, Palanisamy - Solomon, R. V. - Vedha, S. A. - Kolandaivel, P. - Venuvanalingam, P.
The nature of hydrogen bonding in R-2(2)(8) crystal motifs - a computational exploration.
Molecular Physics. Roč. 112, č. 24 (2014), s. 3195-3205. ISSN 0026-8976. E-ISSN 1362-3028
Institutional support: RVO:61388963
Keywords : NCI plot * hydrogen bonds * R-2(2)(8) motif * organic crystals * NBO * QTAIM analysis
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 1.720, year: 2014

R-2(2)(8), a commonly occurring motif in organic crystals, has been examined here through ab initio and density functional theory (DFT) methods. The 11 R-2(2)(8) motifs reported by Allen etal. have been classified into five types; their structural features, hydrogen-bonding patterns and the kind of interactions stabilising these motifs have been studied. Results reveal that the electronegativity of donor atoms plays a major role in directing the hydrogen bonds, whereas their positions in the motif have been found to be less important. Quantum theory of atoms in molecules (QTAIM) and reduced density gradient-based non-covalent-interaction analyses have been used to understand the weak interactions between monomers. Homonuclear interactions within the motifs have been found to be stronger with higher covalent character at the bond critical points than heteronuclear interactions. In addition, a localised molecular orbital energy decomposition analysis (LMOEDA) has been accomplished to provide useful insight into various long- and short-range interactions that contribute to the total stabilisation energies. The stabilising n -> sigma* interactions have been explained using natural bond orbital (NBO) analysis. Overall, this study provides the essential criteria for an organic crystal to be in an R-2(2)(8) motif and further discusses the different combinations of hydrogen-bonding features within the R-2(2)(8) motifs.
Permanent Link: http://hdl.handle.net/11104/0241843