Thermal conductivity of amorphous ices

The thermal conductivities \ensuremath{\kappa} of high-density amorphous (HDA) ice and low-density amorphous (LDA) ice were measured under pressure. The results for HDA show typical glasslike behavior, i.e., positive $d\ensuremath{\kappa}/dT,$ whereas LDA exhibits crystal-like behavior, indicating that phonon-phonon scattering is dominant. LDA appears to be unique among apparently topologically disordered glasses to exhibit such behavior. Moreover, the results imply that LDA and glassy water formed by rapid cooling are different states.