Inorganic Chemistry, Vol.42, No.3, 664-666, 2003
Molecular motions in the solid state: the thermochromic nitro-nitrito interconversion in nickel(II) bis(diamine) complexes
The NO2- ion, in the trans-octahedral [Ni-II(N,N-dimethylethylene-diamine)(2)(NO2)(2)](H2O) complex, coordinates the metal through the nitrogen atom (nitro form). On heating the solid complex, the anion rotates to give nitritc, coordination (oxygen bound), according to a reversible process. The coordination mode of NO2- to Ni-II is related to the steric interplay between the anion and the alkyl substituents on the diamine.