Raman study of solvent–solute interactions in solutions of mercury(II)–thiocyanate complexes

✍ Scribed by S. Šašić; M. Jeremić; A. Antić-Jovanović

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 268 KB
• Volume: 29
• Category: Article
• ISSN: 0377-0486
• DOI: 10.1002/(sici)1097-4555(199804)29:4<321::aid-jrs244>3.0.co;2-q

✦ Synopsis

Raman spectra of the and complex species in solution were investi-Hg(SCN) 2 , [ Hg(SCN) 3 ] -[ Hg(SCN) 4 ] 2gated for 10 donor solvents in the m(CN) and m(CS) wavenumber regions. Attempts were made to relate the solvent donor strength to overall vibrational properties of the complexes. A good correlation of m(CN) with m(HgS) and consequently with solvent donor properties was found in solutions of and [ Hg Wavenumber Hg(SCN) 2 (SCN) 3 ] -. di †erences calculated as the di †erence between wavenumbers of coordinated and free SCN-ligands, Dm8 (CN), correlate well with the solvent donor strength scale, The values for and can D S . Dm8 (CN) Hg(SCN) 2 [ Hg(SCN) 3

]be used as an indicator of solvent donor capacity. Data derived from the Dm(CN) shifts show a better correlation with solvent donor ability than those obtained from the m(CS) wavenumber. The spectral properties of complex depend only on the electrophilic properties of the solvent and not on its donor strength, [ Hg(SCN) 4 ] 2because solvent molecules cannot penetrate into the Ðrst coordination sphere and donate an electron pair to Hg(II). Solvent electrophilic interaction with coordinated thiocyanate is proportional to its acceptor number.