title: 4f-4f absorption spectra and hypersensitivity in nine-coordinate Ho(III) and Er(III) complexes in different environments.
abstract: The effect of change in the environment upon 4f-4f absorption spectra of nine-coordinate Ho(III) and Er(III) complexes with thiocyanate and 2,2'-bipyridyl in methanol, DMSO, DMF and pyridine have been investigated. The oscillator strength for hypersensitive and non-hypersensitive transitions have been calculated and variation in the intensity and band shape with respect to solvent type is rationalized in terms of solvent structure and coordinating properties. A comparison with 1,10-phenanthroline complexes is investigated and has been found that phen has a larger impact on the transition intensities for these ions. Pyridine has been found most effective in promoting 4f-4f intensity. The results indicate that it is important to consider both the static and dynamic coupling mechanism while analysing the oscillator strength of hypersensitive transition.
authors.affiliation: Department of Chemistry, Jamia Millia Islamia, New Delhi 110025, India.
authors.forename: Azad A
authors.initials: AA
authors.lastname: Khan
authors.forename: H A
authors.initials: HA
authors.lastname: Hussain
authors.forename: K
authors.initials: K
authors.lastname: Iftikhar
mesh_terms: D015082:2,2'-Dipyridyl / Q000737:chemistry; D004871:Erbium / Q000737:chemistry*; D006695:Holmium / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry; D010618:Phenanthrolines / Q000737:chemistry; D012997:Solvents; D013053:Spectrophotometry; D055672:Static Electricity; D013861:Thiocyanates / Q000737:chemistry; D014867:Water
chemical_list: D009942:Organometallic Compounds; D010618:Phenanthrolines; D012997:Solvents; D013861:Thiocyanates; D014867:Water; D015082:2,2'-Dipyridyl; D004871:Erbium; D006695:Holmium