This cluster (cluster core only pictured above) is an interesting example from the family of template-centered oxovanadium phosphate clusters.
The template molecule in this case is a water molecule that is bound in the cavity of the cluster through coordination by the oxygen
lone pairs to two vanadyl centers (and trans to the vanadyl oxygens) and through hydrogen bonding between the water protons
and two bridging phenylphosphato oxygens. The vanadyl centers and phosphate bridges form a series eight-membered
O=V(OPO)2V=O rings that envelope the template and show a remarkable degree of conformational flexibility in
"tailor-fitting" the cluster exterior to the shape of the central water molecule. Although the structure is
quite complicated, visualizing it in terms of these bridging rings is a useful starting point in developing an
understanding of the cluster geometry. At the same time, the structural complexity does provide a good example of
the type of messy structural problems that are frequently encountered in the "real world". One might wish, however,
to truncate the structure determination, e.g. omitting terminal phenyl group disorder and included solvent
from the final refinement, so students can complete the structure in a reasonable amount of time.
Literature reference: Bond, M. R., Carrano, C. J., Mokry, L. M., Otieno, T.,
and Thompson, J. "Three New Polynuclear, Di-mu-phosphato Vanadyl Clusters:
[HB(pz)3VO(µ-(C6H5O)2PO2)]2,
[HB(3,5- Me2pz)3VO(µ-(C6H5O)2PO2)]2.C7H8, and
H2O.[t-Bupz(µ-C6H5OPO3)VO]6.2CH3CH2OH.
Adaptability of the Cyclic (OV)(OPO)2(VO) Bridging Unit" Inorg. Chem. 1995, 34, 1894-1905.
Companion Structure: None.
Structure Determination Files by FTP
Download X-ray Data Set (ot36a.hkl)
Download X-ray Data Collection Parameters (ot36a.p4p)
Download Final Refinement Results (ot36a.res)
Last changed December 7, 1996
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