Ab initio studies on hydrogen-bonded chains. III. The linear,infinite chain of hydrogen cyanide molecules

Ab initio crystal-orbital calculations have been performed on the linear, infinite chain of HCN molecules applying basis sets from minimal to double-zeta-plus-polarization quality. From computed potential surfaces many properties of the electronic ground state of (HCN)_∞ could be deduced. Equilibrium structure, hydrogen-bond energy, dipole moment per molecule, dipole-moment derivatives, harmonic force constants, vibrational frequencies and electronic band structure are reported. Results on the polymer are compared with monomer, dimer and crystal data.