ISSN:
1572-8862
Keywords:
Molybdenum tetranuclear cluster
;
rectangular
;
triethylphosphine ligand
;
preparation
;
crystal structure
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Abstract The preparation and structure of the title compound were reported several years ago by McCarly and co-workers ((1978).J. Am. Chem. Soc. 100, 7900). Curiously, it was reported that refinement of the structure converged at exceptionally high figures of merit (R=0.126;R w =0.158), but no reason was given. In view of a recent observation in this laboratory (Chen and Cotton (1991).J. Am. Chem. Soc. 113, 5857) that a similar type of compound, [Re4Cl8(μ-O)2(μ-OMe)2]2− exhibited a subtle but elegant disorder, we reexamined the crystal structure of the title compound. It is found to have 92% of the Mo4 rectangles in one orientation (the only one previously included in the refinement) and 8% in an orientation perpendicular to the main one. In both orientations the ligand positions are approximately the same. The figures of merit are nowR=0.041;R w =0.064. The three structure parameters previously reported are now only slightly different: Mo-Mo=2.210(1) vs. 2.211(3) Å; Mo-Mo'=2.897(1) vs. 2.901(2) Å; angle Mo-Clb-Mo=74.2[8]° vs. 74.4(2)°. We report here the complete structure.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00702953
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