Internally consistent ion volumes and their application in volume-based thermodynamics.

"Volume-based thermodynamics" (VBT) relates the thermodynamics of condensed-phase materials to their formula unit (or molecular) volumes, V(m). In order to secure the most accurate representation of these data, the volumes used are to be derived (in order of preference) from crystal structure data or from density or, in the absence of experimental data, estimated by ion-volume summation.