The crystal structure of (CH3)2NH2MnC13 consists of linear chains of face-sharing MnC16 octahedra which are hydrogen bonded together by the dimethylammonium ions. The Mn-Cl distances range from 2.514 to 2.582 A and the bridging Mn-Cl-Mn angles from 77. 19' to 79.68'. The compound is monoclinic, P2, /c, with a = 8.811{3)A, b = 13.265(4) A, c=6.460(2) A, and P=99.18(2).The magnetic susceptibility shows a broad maximum near 60'K, typical of a one-dimensional antiferromagnet. A fit of the data to a mean-fieldcorrected Fisher model gives an intrachain exchange coupling of -6.9'K and an interchain coupling of -0.5 'K.

[(CH3)3NH]MnCI3.2H20, M= 257.45, orthorhombic, Prima, a = 16.779 (3), b = 7.434 (1), c = 8.227 (l)/~, V= 1026-2 A3, Qo= 1.67 (1) (by flotation in a mixture of CC14 and CH212), Qc = 1.666 gcm -3, Z=4, Mo K0q radiation, 2=0.70926 A,/z(Mo K~)= 19.13 cm -a, F(000)=516, final R=0.051 (all reflections) for the Caputo and Willett data set and 0.029 (observed reflections) for the Muir data set. The structure is comprised of infinite chains of edge-sharing MnCI4(OHz)2 octahedra separated by the trimethylammonium ions and discrete CI ions. It is, in fact, identical with that of the analogous Co compound with minor modifications produced by the difference in ionic radii of the two metal ions.

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The crystal structures of pyridinium manganese(II) chloride monohydrate (PMC) and quinolinium manganese(II) chloride monohydrate (QMC) both contain bi-bridged linear chains. These chains are hydrogen bonded together to form a two-dimensional network. The magnetic susceptibility of QMC is characteristic of a weak antiferromagnet with a maximum in the susceptibility at 2.0 °K. Analysis of the data in terms of a 1-d Heisenberg linear chain gives an intrachain exchange constant of J/k=−0.36 °K. However, the best model includes significant interchain interactions. Thus, both the structural features and magnetic susceptibility indicate that QMC is a perturbed one-diminsional system. This conclusion is supported by previously reported magnetic susceptibility and ESR data for PMC.

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