[Cu(NH3)(2)](NO3)(2) (I) and [Cu(NH3](NO3)(2) (II) were synthesized by interaction of molten NH4NO3 with [Cu(NH3)(4)](NO3)(2) and Cu(NO3)(2) . 3H(2)O, respectively, at 180 to 195 degrees C for 24 hr. According to X-Ray single crystal analysis, I is orthorhombic (sp, gr. Pbca) with a = 5.678(1), b = 9.765(2), c = 11.596(2) Angstrom, Z = 4, R = 0.060; II is monoclinic (sp, gr. P2(1)/c) with a = 6.670(1), b = 8.658(2), c = 9.661(2) Angstrom, beta = 101.78(2)degrees, Z = 4, R = 0.027. In both structures, the nearest coordination environment of Cu is a slightly distorted square formed by N (from NH3) and O atoms (from NO3 groups). The structure of I consists of centrosymmetrical [Cu(NH3)(2)](NO3)(2) molecules linked by hydrogen bonds. The Cu-N and Cu-O distances are 1.98 and 2.01 Angstrom, respectively. In II, the Cu-N distance is 1.95 Angstrom, the Cu-O distances are 1.96, 2.02, and 2.03 Angstrom. The [CuO3NH3] squares are connected by NO3 bridges into zigzag chains, which are linked into layers by longer Cu-O interactions (2.31 Angstrom). Obviously, the layers are additionally strengthened and held together by hydrogen bonds.