Low temperature magneto-structural transitions in Mn3Ni20P6

0459215 - ÚJF 2017 RIV US eng J - Journal Article
Cedervall, J. - Beran, Přemysl - Vennstrom, M. - Danielsson, T. - Ronneteg, S. - Hoglin, V. - Lindell, D. - Eriksson, O. - Andre, G. - Andersson, Y. - Nordblad, P. - Sahlberg, M.
Low temperature magneto-structural transitions in Mn3Ni20P6.
Journal of Solid State Chemistry. Roč. 237, MAY (2016), s. 343-348. ISSN 0022-4596. E-ISSN 1095-726X
R&D Projects: GA MŠMT(CZ) LM2011019
EU Projects: European Commission(XE) 283883 - NMI3-II
Institutional support: RVO:61389005
Keywords : Mn-compounds * magnetic structure * antiferromagnetism * neutron diffraction
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 2.299, year: 2016

X-ray and neutron powder diffraction has been used to determine the crystal and magnetic structure of Mn3Ni20P6. The crystal structure can be described as cubic with space group Fm (3) over barm (225) without any nuclear phase transformation within studied temperature interval from room temperature down to 4 K. The magnetic structure of Mn3Ni20P6 is complex with two independent magnetic positions for the Mn atoms and the compound passes three successive magnetic phase transitions during cooling. At 30 K the spins of the Mn atoms on the Wyckoff 4a site (Mn1) order to form a primitive cubic anti ferromagnetic structure with propagation vector k=(0 0 1). Between 29 and 26 K the Mn atoms on the Wyckoff 8c site (Mn2) order independently on already ordered Mn1 magnetic structure forming a commensurate antiferromagnetic structure with propagation vector k= (0 0 1/2) and below 26 K, both Mn positions order to form an incommensurate helical structure with propagation vector k=(0 0 similar to 0.45). Magnetization vs. temperature curve of Mn3Ni20P6 shows a steep increase indicating some magnetic ordering below 230 K and a sharp field dependent anomaly in a narrow temperature range around 30 K.
Permanent Link: http://hdl.handle.net/11104/0259444