Solvent effects on blue shifted improper hydrogen bond of C-H⋯O in deoxycytidine isomers

► Intra-molecular hydrogen bond networks, which may closely link with their biodiversity and potency as drugs, may hold the key on why the genetic information of DNA/RNA prefers a specific isomer, i.e., 2′-deoxycytidine. ► Blue shifted C-H stretch vibrations of the intra-molecular C−H⋯O hydrogen bond networks are revealed with respect to 2′-deoxycytidine and its isomer 3′-deoxycytidine. ► Solvents interact on nucleosides differently but do not change the nature of the blue shifted C-H vibrations found in gas phase, but reduces the C-H frequencies. ► Polarizability of the solvents affects the H-bond blue-shift in a non-linear relationship to their dielectric constants.