Showing papers by "M. Salah El Fallah published in 1993"

Two new .mu.-azido nickel(II) uniform chains: syntheses, structures, and magneto-structural correlations

Abstract: Two new monodimensional (μ-azido)nickel(II) complexes of formulas catena-(μ-N 3 )[Ni(232-tet)](ClO 4 ) (1) and catena-(μ-N 3 )[Ni(323-tet)](ClO 4 ) (2) have been synthesized and characterized. 232-tet and 323-tet are tetraamines N,N'-bis(2-aminoethyl)-1,3-propanediamine and N,N'-bis(3-aminopropyl)-1,2-ethanediamine, respectively. The crystal structures of 1 and 2 have been solved. The complex [C 7 H 20 N 7 Ni] n (ClO 4 ) n ) (1) crystallizes in the monoclinic system, space group P2 1 /a, with fw=360.44, a=11.806 (3) A, b=13.154(3) A, c=9.598(2) A, β=97.90(2) o , V=1476(1) A 3 , Z=4, R=0.045, and R w =0.055

New dinuclear penta- and hexacoordinated nickel(II) complexes with .mu.-azido bridges. Crystal structures of ferromagnetically coupled (.mu.-N3)2[Ni(Me3[12]N3)]2(ClO4)2.cntdot.2H2O and (.mu.-N3)2[Ni(232-N4)]2(ClO4)2

Abstract: The synthesis, characterization, and properties of the dinuclear Ni(II) complexes (μ-N 3 ) 2 [Ni(Me 3 [12]N 3 )] 2 -(ClO 4 ) 2 .2H 2 O (1), (μ-N 3 ) 2 [Ni(Me 4 [12]N 3 ) 2 (ClO 4 ) 2 .H 2 O (2), and (μ-N 3 ) 2 [Ni(232-N 4 ] 2 (ClO 4 ) 2 (3) are reported. Me 3 [12]N 2 is 2,4,4-trimethyl-1,5,9-triazacyclododec-1-ene, Me 4 [12]N 3 is its 9-methyl derivative, and 232-N 4 is N,N'-bis(2-aminoethyl)-1,3-propanediamine.

Dalton communications. Unusual magnetic and structural one-dimensional nickel(II) azido systems

Abstract: The complexes of general formula [Ni(L)(N3)][ClO4](L is meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane or 2,3-dimethyl-1,4,8,11-tetraazacyclotetradeca-1,3-diene), have been characterized by X-ray crystallography; both are chains in which the nickel(II)–tetraammine fragment is bridged by one µ-azido ligand in trans arrangement, showing unusual magnetic and/or crystallographic properties; preliminary magnetic susceptibility data indicate strong antiferromagnetic coupling.

Unusual magnetic and structural one-dimensional nickel(II) azido systems

Abstract: The complexes of general formula [Ni(L)(N 3 )] [ClO 4 ] (L is meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane or 2,3-dimethyl-1,4,8,11 -tetraazacyclotetradeca-1,3-diene), have been characterized by X-ray crystallography; both are chains in which the nickel(II)-tetraammine fragment is bridged by one μ-azido ligand in trans arrangement, showing unusual magnetic and/or crystallographic properties; preliminary magnetic susceptibility data indicate strong antiferromagnetic coupling