BIS(PHTHALOCYANINATO(2-)RHENIUM(II)) - SYNTHESIS, PROPERTIES, AND CRYSTAL-STRUCTURE

Blue, paramagnetic bis(phthalocyaninato(2-)rhenium(II)) (mu(eff) = 0.8 8 mu(B), per Re, at 300 K) is prepared by thermal decomposition of rip henylphosphine)phthalocyaninato(2-)rhenium(II), in boiling triphenylph osphine, It crystallizes in the triclinic space group P (1) over bar w ith cell parameters as follows: a = 7.799(3) Angstrom, b = 12.563(7) A ngstrom, c = 12.69(1) Angstrom, alpha = 89.97(5)degrees, beta = 94.14( 5)degrees, gamma = 106.39(4)degrees; Z = 1. Two cofacial phthalocyanin ates are bonded together by a Re-Re bond with a Re-Re distance of 2.28 5(2) Angstrom. The Re atoms are located distinctly outside the centre of the (N-iso)(4) planes by 0.426(3) Angstrom. The Re-N-iso distance v aries from 1.99(1) to 2.04(1) Angstrom (average 2.02 Angstrom). The pc (2-) ligands are in an eclipsed conformation and concavely distorted. In the UV-VIS-NIR spectrum the B region is split into two bands of com parable intensity due to strong excitonic coupling, The Re-Re stretchi ng vibration at 240 cm(-1) is selectively enhanced in the resonance Ra man spectrum (lambda(exc) = 488 nm).