Landman, MarileLevell, Tamzyn J.Van Rooyen, Petrus H.Conradie, Jeanet2014-07-292014-07-292014-05Landman, M, Levell, T, Van Rooyen, PH & Conradie, J 2014, 'Conformation analysis of triphenylphosphine in trans and cis triphenylphosphine-substituted Fischer carbene complexes', Journal of Molecular Structure, vol. 1065-1066, no. 1, pp. 29-38.0022-2860 (print)1872-8014 (online)10.1016/j.molstruc.2014.02.014http://hdl.handle.net/2263/40974The synthesis and selected crystal structures of novel (M = Cr or Mo) and known (M =W) [(CO)4(PPh3) M = C(OEt)R] complexes, M = Cr, R = 2-thienyl (1), 2-furyl (2); M = Mo, R = 2-thienyl (3), 2-furyl (4); M = W, R = 2-thienyl (5), 2-furyl (6), are presented. Experimental crystal structures and DFT calculations of selected trans- and cis-triphenylphosphine-substituted Fischer carbene complexes, illustrate that the minimum energy conformation of triphenylphosphine (PPh3) in octahedral [(CO)4(PPh3)ML]-complexes generally have distinct features that can be described in terms of the ‘‘plane of nadir energy’’, a plane linking all points of minimum steric compression between the ligands. The generally observed orientation of PPh3 involves a correlated feathering of the phenyl groups with the PACipso bond of one phenyl group orientated near parallel to the nadir plane, and a meta carbon (Cm) of the other two phenyl groups orientated as near as possible to the nadir plane, orthogonal to the first. Although the orientation of PPh3 in 6-trans, [(CO)4(PPh3)W = C(OEt)2-furyl], deviates from this, DFT correctly calculated the unexpected and not generally observed PPh3 orientation.en© 2014 Elsevier B.V. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in Journal of Molecular Structure. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Molecular Structure, vol.1065-1066, no.1, pp. 29-38, 2014. doi : 10.1016/j.molstruc.2014.02.014.Fischer carbenePhosphineConformational analysisDensity functional theory (DFT)Postprint Article