Monothiocarbamate complexes of Fe(III) have been prepared. (See K. R. Kunze, D. L. Perry...

Monothiocarbamate complexes of Fe(III) have been prepared. (See K. R. Kunze, D. L. Perry, L. J. Wilson, Inorg. hem. , 1977 , 16 , 594.) For the methyl and ethyl complexes, the magnetic moment, µ , is 5.7 to 5.8 µ _B at 300 K; it changes to 4.70 to 5 µ _B at 150 K, and drops still further to 3.6 to 4 µ _B at 78 K. The color changes from red to orange as the temperature is lowered. With larger R groups (propyl, piperidyl, pyrrolidyl), µ > 5.3 µ _B at all temperatures and reater than 6 µ _B in some. Explain these changes. Monothiocarbamate complexes have the following structure.