EPR spectra of Cu2+ and VO2+ ions in ammonium hydrogen oxalate hemihydrate [(NH4)HC2O4 . (1/2)H2O] single crystals.
Cu(2+) and VO(2+) doped ammonium hydrogen oxalate hemihydrate, [(NH(4))HC(2)O(4) . (1/2)H(2)O], single crystals have been studied at room temperature and at 113K in three mutually perpendicular planes. Both ions yield unexpectedly large number of lines. The calculated results of the Cu(2+) and VO(2+) doped in [(NH(4))HC(2)O(4) . (1/2)H(2)O] indicate that both ions substitute with the NH(4)(+) ion in the structure. The EPR spectra of Cu(2+) ions are characteristic of tetragonally elongated octahedral site and the spectra of VO(2+) are characteristic of tetragonally compressed complex. The angular variation of the EPR spectra has shown that two different Cu(2+) and VO(2+) complexes are located in different chemical environments, and each environment contains two magnetically inequivalent Cu(2+) and VO(2+) sites in distinct orientations occupying substitutional positions in the lattice and show very high angular dependence. The principal g and the hyperfine (A) values of both ions are determined.
Ondokuz Mayis University, Faculty of Arts and Sciences, Department of Physics, 55139 Samsun, Turkey. bbulut@omu.edu.tr
Bünyamin
B
Karabulut
Ayşe
A
Tufan
D002412:Cations / Q000032:analysis; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003300:Copper / Q000032:analysis / Q000737:chemistry*; D003460:Crystallization; D004578:Electron Spin Resonance Spectroscopy; D008433:Mathematics; D015394:Molecular Structure; D010070:Oxalates / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D014638:Vanadates / Q000032:analysis / Q000737:chemistry*
D002412:Cations; D010070:Oxalates; D000644:Quaternary Ammonium Compounds; C517490:ammonium hydrogen oxalate hemihydrate; D014638:Vanadates; D003300:Copper