Effects of d-orbital occupancy on the geometry of the trigonal-bipyramidal complexes [MIICl3(Hdabco)(dabco)]n, where M is Mn, Co, Ni or Cu and dabco is 1,4-diazabicyclo[2.2.2]-octane

Geometric data from (1-aza-4-azoniabicyclo[2.2.2]octane-κN 1)(1,4-diazabicyclo[2.2.2]octane-κN1) trichloromanganese(II), [MnCl3(C6H13N 2)(C6H12N2)] or [MnCl 3(Hdabco)(dabco)] (dabco is 1,4-diazabicyclo[2.2.2]octane), and the cobalt(II) analogue, [CoCl3(C6H13N 2)(C6H12N2)], have been combined with previously reported data for the Ni and Cu analogues to show that bond-length trends across the isotypal series are consistent with a high-spin trigonal-bipyramidal system. As each transition metal is positioned on a D 3 site in the space group R32 (No. 155), two bond lengths fully define each trigonal-bipyramidal coordination geometry [Mn-Cl = 2.3903 (7) Å and Mn-N = 2.367 (2) Å, and Co-Cl = 2.3080 (8) Å and Co-N = 2.269 (3) Å]. © 2006 International Union of Crystallography.