A copper(II) complex with a Cu-S-8 bond. Attenuated total reflectance, electron paramagnetic resonance, resonance Raman and atoms-in-molecule calculations

作者：Shee Nirmal K; Adekunle Florence A O; Verma Ravi; Kumar Devesh; Datta Dipankar^*

来源：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , 2015, 151: 96-99.

DOI：10.1016/j.saa.2015.06.065

• Copper(II)
• Elemental sulfur
• DFT
• EPR
• Resonance Raman

Green [Cu(1,10-phenanthroline)(2)OH2](ClO4)(2) (1) reacts with yellow elemental sulfur at room temperature in methanol to yield turquoise blue [Cu(1,10-phenanthro-line)(2)(S-8)](ClO4)(2) (2). A comparative study of the EPR spectra of 1 and 2 in solid state and in methanol glass indicates that the S-8 unit in 2 is bound to the metal. High level DFT calculations show that the cation in 2 is five coordinate, distorted square pyramidal with S-8 occupying the apical position. The crucial Cu(II)-S bond is around 2.9 angstrom. Such long Cu(II)-S bonds occur in oxidized plastocyanin where it is considered to be bonding. Presence of a weak Cu-S-8 bond is revealed in the resonance Raman spectra of 2. Satisfactory matching of the calculated and experimental IR spectra vindicates the theoretically derived structure of the cation in 2.

• 出版日期2015-12-5