Tetrakis(1-ethyl-1H-1,2,4-triazole-kappaN4)bis(nitrato-kappaO)copper(II) and bis(nitrato-kappaO)tetrakis(1-propyl-1H-1,2,4-triazole-kappaN4)copper(II).

The copper(II) environments for tetrakis(1-ethyl-1,2,4-triazole)dinitratocopper(II), [Cu(NO3)2(C4H7N3)4], and tetrakis(1-propyl-1,2,4-triazole)dinitratocopper(II), [Cu(NO3)2(C5H9N3)4], are distorted square bipyramidal. Both structures are centrosymmetric, with the copper(II) ions located at inversion centers coordinated by four N atoms of four triazole molecules and by two O atoms of two nitrate ions in an elongated octahedral geometry. This elongation is a result of the Jahn-Teller effect. The largest distortion is that of the N-Cu-O angles, which differ from 90 degrees by 5.68 (10) degrees in the ethyl and 5.59 (8) degrees in the propyl derivative.