Coexistence of Long-Range Ferromagnetic Ordering and Glassy Behavior in One-Dimensional Bimetallic Cyano-Bridged Polymers

Two new one-dimensional (1-D) 3d−5d cyano-bridged bimetallic assemblies, {[Co3II(DMF)12][WV(CN)8]2]}∞ (1) and
{[Mn3II(bipy)2(DMF)8][WV(CN)8]2}∞ (2), have been synthesized and characterized, where bipy stands for 2,2‘-bipyridine
and DMF represents N,N-dimethylformamide. The X-ray analyses show that the two complexes belong to the P1̄
space group with Z = 1 and C52H84N28O12Co3W2, a = 11.690(3) Å, b = 12.703(3) Å, c = 13.712(3) Å, α =
86.889(4)°, β = 73.256(4)°, and γ = 77.033(4)° for 1 and C60H72N28O8Mn3W2, a = 10.672(2) Å, b = 13.024(3)
Å, c = 16.000(3) Å, α = 78.32(3)°, β = 75.69(3)°, and γ = 66.63(3)° for 2. The structures of the two complexes
are similar and consist of 12-atom rhombic M2W2(CN)4 (M = Co (1), Mn (2)) units, which act as a basic component
to be repeatedly connected through W−C−N−M−N−C−W linkages to form a one-dimensional infinite 3,2-chain;
these chains are well separated by the DMF molecules or 2,2‘-bipyridines coordinated to the metal ions Co2+ for
1 and Mn2+ for 2. Magnetic studies, including linear and nonlinear ac susceptibility measurements, demonstrate
that the long-range magnetic ordering and spin glass behavior coexist in the two 1-D compounds.