The thermal properties of lanthanide hydrazidocarbonates were studied
in an inert atmosphere by selecting neodymium hydrazidocarbonate trihy
drate, Nd(N2H3COO)3. 3H2O, as a model substance for the essentially si
milar thermal behaviour of hydrazidocarbonates of all the lanthanides
except promethium. Neodymium hydrazidocarbonate trihydrate cannot be c
onverted into a pure anhydrous compound by heat treatment because the
dehydration of the sample is accompanied by partial decomposition of t
he other part of the molecule, i.e. the hydrazidocarbonato groups. The
decomposition finally proceeds through some intermediates to a mixtur
e of neodymium oxide and amorphous carbon, and finally at 1450-degrees
-C, to neodymium oxide carbide, Nd2C2O2.