TRANS-[NI(333-TET)(MU-N3)]N(CLO4)N AND CIS-[NI(333-TET)(MU-N3)]N(PF6)N - 2 NOVEL KINDS OF STRUCTURAL NICKEL(II) CHAINS WITH A SINGLE AZIDO BRIDGE - MAGNETIC-BEHAVIOR OF AN ALTERNATING S=1 CHAIN WITH ALPHA=0.46
A. Escuer et al., TRANS-[NI(333-TET)(MU-N3)]N(CLO4)N AND CIS-[NI(333-TET)(MU-N3)]N(PF6)N - 2 NOVEL KINDS OF STRUCTURAL NICKEL(II) CHAINS WITH A SINGLE AZIDO BRIDGE - MAGNETIC-BEHAVIOR OF AN ALTERNATING S=1 CHAIN WITH ALPHA=0.46, Inorganic chemistry, 33(9), 1994, pp. 1842-1847
The compounds trans-[Ni(333-tet)(mu-N3)]n(ClO4)n (1) and cis-[Ni(333-t
et)(mu-N3)]n(PF6)n(2) in which 333-tet is the tetraamine N,N'-bis(3-am
inopropyl)-1,3-propanediamine have been synthesized and characterized.
1 crystallizes in the triclinic system, space group P1BAR, with fw =
388.50, a = 8.765(1) angstrom, b = 8.976(1) angstrom, c = 11.995(2) an
gstrom, alpha = 106.65(1)degrees, beta = 110.06(1)degrees, gamma = 91.
11(1)degrees, V = 842.0(2) angstrom3, Z = 2, R = 0.047, and R(w) = 0.1
30. The nickel atom is placed in an octahedral environment with the br
idging azido groups in a trans arrangement. Two kinds of alternating c
entrosymmetric azido bridges, both coordinated in end-to-end fashion,
are present in the chain, for which the Ni-N bond distance and Ni-N-N
bond angle are 2.077(3) angstrom, 142.4(3)degrees and 2.204(3) angstro
m, 123.6(2)degrees, respectively, giving an unusual alternating system
. 2 crystallizes in the orthorhombic system, space group P2(1)2(1)2(1)
, with fw = 434.03, a = 15.7 36(3) angstrom, b = 13.607(3) angstrom, c
= 8.182(2) A, v = 1751.9(7) angstrom3, Z = 4, R = 0.062, and R(w) = 0
.154. The nickel atom is placed in an octahedral environment with the
end-to-end azido bridges in an unprecedented cis arrangement. Magnetic
measurements show a strong antiferromagnetic coupling for 1, where J
= -80.7 cm-1, alpha = 0.46, and g = 2.40, and lower coupling for 2, wh
ere J = -18.5 cm-1 and g = 2.29. The magnetic behavior of both compoun
ds has been correlated with the bond parameters.