caa a22 4500 463240154 CHVBK 20180405153310.0 cr unu---uuuuu 170326e20070901xx s 000 0 eng 10.1007/s10947-007-0124-7 doi (NATIONALLICENCE)springer-10.1007/s10947-007-0124-7 Mashkovtsev R. Institute of Geology and Mineralogy, Siberian Division, Russian Academy of Sciences, Novosibirsk aut Paramagnetic centers related to Al, Sc, In, and Nb impurities in KTiOAsO4crystals [Elektronische Daten] [R. Mashkovtsev] Electron paramagnetic resonance (EPR) is applied to study Al-, Sc-, In-, and Nb-doped KTiOAsO4 (KTA) crystals. Paramagnetic hole centers O− are observed after ionizing irradiation of KTA crystals. These centers are, as a rule, unstable at room temperature and are slowly annealed for about two weeks. Oxygen ions are bridging two cations in KTA. Near the impurity, two p-orbitals of oxygen atoms participate in covalent bonding with cations, whereas the third p-orbital remains free and under the radiation effect captures the hole thus forming the paramagnetic center of M n+-O−-M(n−1)+ (here M n+ is the lattice cation and M(n−1)+ is the impurity cation of Al, In, Sc, or Nb). In the centers investigated the specific principal direction of the g-factor g ∼ 2 is normal to the M n+-O−-M(n−1)+ plane, and the main value of g max falls in this plane. The direction of the O−-M(n−1)+ bond is close to the selected direction of the hyperfine interaction with the impurity ion. The models of six hole centers and the found parameters of EPR spectra are discussed. Springer Science+Business Media, Inc., 2007 EPR nationallicence hole centers nationallicence KTiOAsO4 (KTA) nationallicence Journal of Structural Chemistry Springer US 48/5(2007-09-01), 831-839 0022-4766 48:5<831 2007 48 10947 https://doi.org/10.1007/s10947-007-0124-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10947-007-0124-7 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Mashkovtsev R. Institute of Geology and Mineralogy, Siberian Division, Russian Academy of Sciences, Novosibirsk aut NATIONALLICENCE 773 0- Journal of Structural Chemistry Springer US 48/5(2007-09-01), 831-839 0022-4766 48:5<831 2007 48 10947 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer