Abstract
The thermosalient transformation in nickel(II) bis(diisopropyl)dithiocarbamate has been investigated using selective deuteration. The deuterated crystals undergo a reversible displacive phase transition that is ∼4 K higher in temperature compared to the protonated analogue. Neutron, synchrotron, density-functional theory, and calorimetric techniques were utilized to demonstrate the substantial effect of deuterium. All techniques demonstrated the equivalence of the mechanism on an atomic scale between the protonated and deuterated complexes. The data collected in this study reveal details of the changes of atomic motion that underpin the thermosalience inherent in this system. Deuterium decreased the frequency of atomic vibrations thus increasing the temperature of the observed transformation. This study represents a key advancement in the field of thermosalient molecular systems and provides insights into the control and manipulation of thermosalient materials.