Тип публикации: статья из журнала
Год издания: 2005
Аннотация: The high-pressure magnetic states of iron borate 57 FeBOs single crystal and powder samples have been investigated in diamond anvil cells by nuclear forward scattering (NFS) of synchrotron radiation at different temperatures. In the low-pressure (0 < P < 46 GPa) antiferromagnetic phase, an increase of the Neel temperature from 350 to 595 К induced by pressure was found. At pressures 46-49 GPa, a transition from the antiferromagnetic to a new magnetic state with a weak magnetic moment (magnetic collapse) was discovered. It is attributed to the electronic transition in Fe3+ ions from the high-spin 3d5 (S = 5/2, 6Aig) to the low-spin (S = 1/2, 2Тгg) state (spin crossover) due to the insulator-semiconductor-type transition with extensive suppression of strong d-d electron correlations. At low temperatures, NFS spectra of the high-pressure phase indicate magnetic correlations in the low-spin system with the magnetic ordering temperature about 50 К. А tentative magnetic P-T phase diagram of FeBOs is proposed. An important feature of this diagram is the presence of two triple points where magnetic and paramagnetic phases of the high-spin and low-spin states coexist.
Журнал: Журнал экспериментальной и теоретической физики
Выпуск журнала: Т. 127, № 4
Номера страниц: 780-789
ISSN журнала: 00444510
Место издания: Москва
Издатель: Российская академия наук, Институт физических проблем им. П.Л. Капицы РАН