Tetrakis(1-ethyl-1H-1,2,4-triazole-κN4)bis(nitrato-κO)copper(II) and bis(nitrato-κO)tetrakis(1-propyl-1H-1,2,4-triazole-κN4)copper(II)

The copper(II) environments for tetrakis(1-ethyl-1,2,4-triazole)dinitratocopper(II), [Cu(NO 3 ) 2 (C 4 H 7 N 3 ) 4 ], and tetrakis-(1-propyl-1,2,4-triazole)dinitratocopper(II), [Cu(NO 3 ) 2 (C 5 -H 9 N 3 ) 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 by 5.68 (10)° in the ethyl and 5.59 (8)° in the propyl derivative.