X-ray structure determination of Ru(TPP)(CO)(Melm)center dot 2CHCl(3)

The crystal structure of (carbonyl)(1-methylimidazole)(5,10,15,20 nium(II). 2chloroform, Ru(TPP)(CO)(MeIm). 2CHCl(3). an R-state model of the hemoglob in active site, has been determined. The material crystallizes in space gro up P2(1)/c of the monoclinic system with four formula units in a cell of di mensions a = 12.733(2) Angstrom, b = 14.535(2) Angstrom, c = 24.921(2) Angs trom, beta = 91.15(1)degrees at T = 1 10 K. The structure has been refined to R(F)= 0.038 for 588 variables and 7458 data. The Ru-C(O) distance is 1.8 35(3) Angstrom and the Ru-N((imidazole)) distance is 2.163(2) Angstrom. Thi s is the third reported crystal structure of a solvated Ru(TPP)(CO)(MeIm) c ompound. It differs from the other two in a larger displacement of 0.079(1) Angstrom of the Ru atom from the mean porphyrin plane toward the CO ligand , a shorter RU-N-(imidazole) bond, a smaller average deviation, 0.06 Angstr om, of atoms from the porphyrin plane, and the absence of a small less than or equal to 60 degrees dihedral angle between the porphyrin plane and phen yl rings. Copyright (C) 2001 John Wiley & Sons, Ltd.