Reaction of sodium azide with manganese(II) and pyridine derivatives such as 2-bzpy, 3-bzpy, and 3,5lut (2-benzoylpyridine, 3-benzoylpyridine, and 3,5-dimethylpyridine, respectively) led to the one-dimensional systems
cis-[Mn(2-bzpy)(N3)2]
n
(1), trans-[Mn(3-Bzpy)2(N3)2]
n
(2), and cis-[Mn(3,5lut)2(N3)2]
n
(3). Compound 1 crystallizes
in the P21/n group: a = 14.413(4) Å, b = 16.157(4) Å, c = 18.478(5) Å, and Z = 12. Compound 2 crystallizes
in the C2/c group: a = 14.179(5) Å, b = 9.698(4) Å, c = 34.351(12) Å, and Z = 8. Compound 3 crystallizes
in the P21/n group: a = 13.552(6) Å, b = 7.730(3) Å, c = 16.554(6) Å, and Z = 4. Structural determination
shows a chain with double μ1,1 azido bridges for 1, an alternating system with double μ1,1 and μ1,3 azido bridges
for 2, and finally a chain with double μ1,3 azido bridges for 3. Susceptibility data show ferromagnetic coupling
for 1, antiferromagnetic coupling for 3, and alternating ferro−antiferromagnetic interactions for 2. EPR data
measured on powdered samples and single crystals show the ideal Heisenberg narrowing angular dependence for
the three kinds of coupled systems and an increasing dipolar broadening mechanism in the order 3 < 2 < 1
according to the decreasing Mn···Mn intrachain distances.
