"Filip, Jan" . "Kohout, Tom\u00E1\u0161" . . "0003-004X" . "10.2138/am.2013.4348" . "magnetism; Alabandite (MnS), hausmannite (Mn3O4), troilite (FeS)"@en . . . "\u010Cuda, Jan" . . . "15310" . "Med\u0159\u00EDk, Ivo" . "8-9" . "5"^^ . "Low-temperature magnetism of alabandite: Crucial role of surface oxidation" . "98" . . "7"^^ . . "American Mineralogist" . "10"^^ . "000323584000020" . . . . "Santala, Eero" . "[4DF1690968B6]" . . . . "Low-temperature magnetism of alabandite: Crucial role of surface oxidation" . . "Skala, Roman" . "Manganese(II) monosulphide crystallizes into three different polymorphs (alpha-, beta-, and gamma-MnS). Out of these, alpha-MnS, also known as mineral alabandite, is considered the most stable and is widespread in terrestrial materials as well as in extraterrestrial objects such as meteorites. In this study, a low-temperature antiferromagnetic state of alpha-MnS was investigated using macroscopic magnetic measurements as induced and remanent field-cooled (FC) and zero-field-cooled (ZFC) magnetizations and magnetic hysteresis. Both natural alabandite and synthetic samples show: (1) Neel temperatures in a narrow temperature range around 153 K, and (2) a rapid increase of the magnetization around 40 K. An anomalous magnetic behavior taking place at about 40 K was previously ascribed to the magnetic transition from a high-temperature antiferromagnetic to a low-temperature ferromagnetic state documented for non-stoichiometric alpha-MnS slightly enriched in manganese. However, our detailed microscopic observations and, in particular, oxidation experiments indicate that the anomalous magnetic behavior around 40 K is caused by the presence of an oxide layer of ferrimagnetic hausmannite (Mn3O4) on the surface of alpha-MnS rather than being an intrinsic property of nearly stoichiometric alpha-MnS."@en . "Low-temperature magnetism of alabandite: Crucial role of surface oxidation"@en . "http://ammin.geoscienceworld.org/content/98/8-9/1550" . . "US - Spojen\u00E9 st\u00E1ty americk\u00E9" . "Zbo\u0159il, Radek" . . "Low-temperature magnetism of alabandite: Crucial role of surface oxidation"@en . . "Manganese(II) monosulphide crystallizes into three different polymorphs (alpha-, beta-, and gamma-MnS). Out of these, alpha-MnS, also known as mineral alabandite, is considered the most stable and is widespread in terrestrial materials as well as in extraterrestrial objects such as meteorites. In this study, a low-temperature antiferromagnetic state of alpha-MnS was investigated using macroscopic magnetic measurements as induced and remanent field-cooled (FC) and zero-field-cooled (ZFC) magnetizations and magnetic hysteresis. Both natural alabandite and synthetic samples show: (1) Neel temperatures in a narrow temperature range around 153 K, and (2) a rapid increase of the magnetization around 40 K. An anomalous magnetic behavior taking place at about 40 K was previously ascribed to the magnetic transition from a high-temperature antiferromagnetic to a low-temperature ferromagnetic state documented for non-stoichiometric alpha-MnS slightly enriched in manganese. However, our detailed microscopic observations and, in particular, oxidation experiments indicate that the anomalous magnetic behavior around 40 K is caused by the presence of an oxide layer of ferrimagnetic hausmannite (Mn3O4) on the surface of alpha-MnS rather than being an intrinsic property of nearly stoichiometric alpha-MnS." . . . . "RIV/61989592:15310/13:33144971!RIV14-GA0-15310___" . "Haloda, Jakub" . . "I, P(ED2.1.00/03.0058), P(GAP108/11/1350), P(KJB300130903), S" . "Tu\u010Dek, Ji\u0159\u00ED" . . "Kosterov, Andrei" . . "RIV/61989592:15310/13:33144971" . . . "85512" .