arXiv subjects

N. B. Ivanova

Publications and source records attributed to N. B. Ivanova.

2 recordsLinked to original sources

arXiv2015

Crystal and local atomic structure of Co-doped MgFeBO_4 warwickites

Single crystalline MgFeBO_4, Mg_0.5Co_0.5FeBO_4 and CoFeBO_4 have been grown by the flux method. The samples have been characterized by X-ray spectral analysis, X-ray diffraction and X-ray absorption spectroscopy. The X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra have been measured at the Fe andCoK-edges over a wide temperature range (6.5 - 300 K). The composition, the charge state and local environment of both Fe and Co atoms have been determined. The effects of Mg substitution by Co on the local structural distortions have been revealed experimentally and the M-O bond anisotropy has been found.

cond-mat.mtrl-sci↗

arXiv2015

Uniaxial anisotropy and low-temperature antiferromagnetism of Mn2BO4 single crystal

The Mn2BO4 single crystals have been grown using the flux technique. The careful study crystal structure and magnetic properties have been carried out. The antiferromagnet transition at TN = 26 K has been traced through the dc magnetization and specific heat temperature dependences. The magnetic uniaxial anisotropy has been detected with easy axis of magnetization lying in ab-plane. A reduction of the effective magnetic moment value is assigned to the non-quenched orbital moment of Jahn-Teller Mn3+ ions. Based on the superexchange interactions calculations the magnetic behavior is discussed.

cond-mat.str-el↗