In the second year inorganic lab course you prepare and then examine the vibrational spectra of the isomers of Mo(CO)4L2 where L=PPh3 or L=piperidine (HNC5H10). The number of CO vibrational bands active is related to the symmetry of the complex, four carbonyl absorption bands are expected from the compound with cis ligands and only one band is expected from the compound with trans ligands. Because the phenyl rings are too expensive to compute we will replace them with the less computationally demanding CH3 groups.
Your job is going to be to use calculations to predict the thermal stability and spectral characteristics of two cis or trans isomers. Record key information in your wiki and answer the questions below. There are also some references given at the bottom of this page.
ref2 "Intramolecular hydrogen bonding and cation π-interactions affecting cis to trans isomerization in tungsten hexacarbonyl derivatives of 2-pyridyldiphenylphosphane and triphenylphosphane", Leeni Hirsivaara, Matti Haukka and Jouni Pursiainen, Inorg. Chem. Comm., 3 (2000) p508-510
ref3 "The crystal and molecular structure of trans-tetracarbonylbis(triphenyl-phosphine)chromium(0) in a new unit cell: Is the trans conformer more stable than the cis?", Dennis W. Bennett, Tasneem A. Siddiquee, Daniel T. Haworth, Shariff E. Kabir and Farzana Camellia. J. Chem. Cryst., 34 (6) (2004) p353-359