An Experimental Exploration of C‐H· · ·X Hydrogen Bond in [CHCl3‐X(CH3)2] Complexes (X = O, S, and Se)

Among the conglomeration of hydrogen bond donors, the C-H group is prevalent in chemistry and biology. In the present work, CHCl3 has been selected as the hydrogen bond donor and X(CH3)2 are the hydrogen bond acceptors. Formation of C-H· · ·X hydrogen bond under the matrix isolation condition is confirmed by the observation of red-shift in the C-H stretching frequency of CHCl3 and comparison with the simulated spectra. Stabilisation energy of all the three complexes is almost equal although the observed red-shift for the C-H· · ·O complex is less compared to the C-H···S/Se complexes. The nature and origin of the hydrogen bond have been delineated using Natural Bond Orbital, Atoms in Molecules, Non-Covalent Interaction analyses, and Energy Decomposition Analysis. Charge transfer is found to be proportional to the observed red-shift. This work provides the first impressions of C-H···Se hydrogen bond and its comparison with C-H· · ·O/S hydrogen bond interaction under experimental condition.