Liquid water as a lone-pair amorphous semiconductor

Abstract

We approximate liquid water as a lone-pair amorphous semiconductor. Since electronic orbital times are short compared to the periods of atomic and molecular motion, properties dependent on electronic states can be interpreted to determine short-time intermediate range order. An anomalous temperature dependence of the Urbach exponential absorption edge for intramolecular electronic excitation is noted and interpreted in terms of the perturbation of the lone-pair valence band by hydrogen bonding. The extrinsic optical absorptions with I− and Br− doped water are observed to have Urbach tails. An approximate electronic band structure for pure and doped liquid water is presented.