화학공학소재연구정보센터
Inorganic Chemistry, Vol.38, No.9, 2085-2092, 1999
Resonance Raman, X-ray crystallographic, and magnetic susceptibility studies of metal-metal-bonded MoRu and WOs porphyrin dimers. 1. Evidence for an unusual MO diagram
Solution (VT NMR, Evans method magnetic susceptibility, resonance Raman) and solid-state (SQUID magnetic susceptibility, X-ray crystallography) spectroscopic studies of intertriad heterodimeric [(OEP)MoRu(OEP)] (1), [(OEP)WOs(OEP)] (2), and [(OEP)MoRu(TPP)]PF6 (3(+)) metalloporphyrins are reported (OEP = 2,3,7,8,12,13,17,18-octaethylporphyrinato; TPP = 5,10,1 5,20-tetraphenylporphyrinato). Solution and solid-state magnetic susceptibility data indicate that 1 and 2 contain two unpaired electrons in the ground electronic configuration. The presence of a delta bond in 3(+) has been confirmed by structural characterization: The experimental evidence is consistent with a molecular orbital ordering, sigma < pi < delta < pi* < delta*, which is different from that seen for homologous metalloporphyrin dimers with homometallic or intratriad heterometallic multiple metal-metal bonds. Resonance Raman data suggest that the heterometallic bonds are slightly stronger than isoelectronic homometallic species.