PASCal: a principal axis strain calculator for thermal expansion and compressibility determination

The web-based program PASCal (http://pascal.chem.ox.ac.uk) is introduced as a tool for determining principal coefficients of thermal expansion and compressibilities using variable-pressure and variable-temperature lattice parameter data. The additional scientific insight provided by this analysis is illustrated with reference to three case studies: the metal–organic framework Cu-SIP-3, the molecular crystal β-HMX and the mineral malayaite.