\"NdMn6-xFexGe6 , SmMn6-xFexGe6 , NdMn6-xFexSn6 , and SmMn6-xFexSn6 have been studied by x-ray and neutron diffraction techniques and bulk magnetization measurements. NdMn6-xFe6Sn6 has also been studied by Mӧssbauer spectroscopy. All germanides crystallize in the disordered YCo6Ge6-type structure, whereas the stannides crystallize in the HoFe6Sn6-type and the TbFe6Sn6-type structure for the non-substituted samples and the iron-containing samples, respectively. Iron randomly replaces manganese on all sites in both germanides and stannides. The a, b, and c lattice parameters decrease with increasing iron content for all samples. The net magnetization decreases with increasing iron content for all germanides and the stannides with iron content larger than x = 1.24, whereas the net magnetization increases with increasing iron content for the stannides with iron content less than x = 1.24. The magnetic moment of the iron sublattice couples antiferromagnetically with the ferromagnetically coupled manganese and rare-earth moments for the germanides, whereas there is ferromagnetic coupling between the iron sublattice and the ferromagnetically coupled manganese and rare-earth sublattices for the stannides. Spin reorientation occurs in all neodymium- containing samples in which the easy magnetization direction cants away from the c-axis and the a-axis with increasing temperature for the germanides and the stannides, respectively. The easy magnetization direction of all samarium-containing samples is parallel to, or at least aligned at a small angle with, the basal plane of the unit cell at room temperature. An analysis of the Mn-Mn interatomic distances in RMn6X6 and RMn6-xFexX6, where R is a rare earth and X is germanium or tin, indicates that there is a critical Mn-Mn distance, dT ≈ 2.6145 Å, below and above which the coupling within the manganese sublattice is anti ferromagnetic and ferromagnetic, respectively\"--Abstract, page iv.
","abstract_html":"<p>"NdMn<sub>6-x</sub>Fe<sub>x</sub>Ge<sub>6</sub> , SmMn<sub>6-x</sub>Fe<sub>x</sub>Ge<sub>6</sub> , NdMn<sub>6-x</sub>Fe<sub>x</sub>Sn<sub>6</sub> , and SmMn<sub>6-x</sub>Fe<sub>x</sub>Sn<sub>6</sub> have been studied by x-ray and neutron diffraction techniques and bulk magnetization measurements. NdMn<sub>6-x</sub>Fe<sub>6</sub>Sn<sub>6</sub> has also been studied by Mӧssbauer spectroscopy. All germanides crystallize in the disordered YCo<sub>6</sub>Ge<sub>6</sub>-type structure, whereas the stannides crystallize in the HoFe<sub>6</sub>Sn<sub>6</sub>-type and the TbFe<sub>6</sub>Sn<sub>6</sub>-type structure for the non-substituted samples and the iron-containing samples, respectively. Iron randomly replaces manganese on all sites in both germanides and stannides. The a, b, and c lattice parameters decrease with increasing iron content for all samples. The net magnetization decreases with increasing iron content for all germanides and the stannides with iron content larger than x = 1.24, whereas the net magnetization increases with increasing iron content for the stannides with iron content less than x = 1.24. The magnetic moment of the iron sublattice couples antiferromagnetically with the ferromagnetically coupled manganese and rare-earth moments for the germanides, whereas there is ferromagnetic coupling between the iron sublattice and the ferromagnetically coupled manganese and rare-earth sublattices for the stannides. Spin reorientation occurs in all neodymium- containing samples in which the easy magnetization direction cants away from the c-axis and the a-axis with increasing temperature for the germanides and the stannides, respectively. The easy magnetization direction of all samarium-containing samples is parallel to, or at least aligned at a small angle with, the basal plane of the unit cell at room temperature. An analysis of the Mn-Mn interatomic distances in RMn<sub>6</sub>X<sub>6</sub> and RMn<sub>6</sub>-<sub>x</sub>Fe<sub>x</sub>X<sub>6</sub>, where R is a rare earth and X is germanium or tin, indicates that there is a critical Mn-Mn distance, d<sub>T</sub> ≈ 2.6145 Å, below and above which the coupling within the manganese sublattice is anti ferromagnetic and ferromagnetic, respectively"--Abstract, page iv.</p>","abstract_has_math":false,"creators":["Han, Jun"],"institution":"University of Missouri--Rolla","degree_name":"Ph. D. in Chemistry","degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016-02-10T08:00:00Z","date_published":"2016-02-10T08:00:00Z","updated_at":"2026-07-24T03:19:38Z","subjects":["Chemistry"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarsmine.mst.edu/doctoral_dissertations/1364","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Han, Jun"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2016-02-10T08:00:00Z"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation - Restricted Access"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph. D. in Chemistry"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Missouri--Rolla"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Chemistry"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarsmine.mst.edu/doctoral_dissertations/1364"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["\"NdMn6-xFexGe6 , SmMn6-xFexGe6 , NdMn6-xFexSn6 , and SmMn6-xFexSn6 have been studied by x-ray and neutron diffraction techniques and bulk magnetization measurements. NdMn6-xFe6Sn6 has also been studied by Mӧssbauer spectroscopy. All germanides crystallize in the disordered YCo6Ge6-type structure, whereas the stannides crystallize in the HoFe6Sn6-type and the TbFe6Sn6-type structure for the non-substituted samples and the iron-containing samples, respectively. Iron randomly replaces manganese on all sites in both germanides and stannides. The a, b, and c lattice parameters decrease with increasing iron content for all samples. The net magnetization decreases with increasing iron content for all germanides and the stannides with iron content larger than x = 1.24, whereas the net magnetization increases with increasing iron content for the stannides with iron content less than x = 1.24. The magnetic moment of the iron sublattice couples antiferromagnetically with the ferromagnetically coupled manganese and rare-earth moments for the germanides, whereas there is ferromagnetic coupling between the iron sublattice and the ferromagnetically coupled manganese and rare-earth sublattices for the stannides. Spin reorientation occurs in all neodymium- containing samples in which the easy magnetization direction cants away from the c-axis and the a-axis with increasing temperature for the germanides and the stannides, respectively. The easy magnetization direction of all samarium-containing samples is parallel to, or at least aligned at a small angle with, the basal plane of the unit cell at room temperature. An analysis of the Mn-Mn interatomic distances in RMn6X6 and RMn6-xFexX6, where R is a rare earth and X is germanium or tin, indicates that there is a critical Mn-Mn distance, dT ≈ 2.6145 Å, below and above which the coupling within the manganese sublattice is anti ferromagnetic and ferromagnetic, respectively\"--Abstract, page iv.
"]},{"key":"dc:title","label":"Title","values":["The atomic and magnetic structures of several iron-substituted rare-earth manganese germanides and stannides"]}]}],"canonical_facts":{"dc:creator":["Han, Jun"],"dc:date.available":["2016-02-10T08:00:00Z"],"dc:description.abstract":["\"NdMn6-xFexGe6 , SmMn6-xFexGe6 , NdMn6-xFexSn6 , and SmMn6-xFexSn6 have been studied by x-ray and neutron diffraction techniques and bulk magnetization measurements. NdMn6-xFe6Sn6 has also been studied by Mӧssbauer spectroscopy. All germanides crystallize in the disordered YCo6Ge6-type structure, whereas the stannides crystallize in the HoFe6Sn6-type and the TbFe6Sn6-type structure for the non-substituted samples and the iron-containing samples, respectively. Iron randomly replaces manganese on all sites in both germanides and stannides. The a, b, and c lattice parameters decrease with increasing iron content for all samples. The net magnetization decreases with increasing iron content for all germanides and the stannides with iron content larger than x = 1.24, whereas the net magnetization increases with increasing iron content for the stannides with iron content less than x = 1.24. The magnetic moment of the iron sublattice couples antiferromagnetically with the ferromagnetically coupled manganese and rare-earth moments for the germanides, whereas there is ferromagnetic coupling between the iron sublattice and the ferromagnetically coupled manganese and rare-earth sublattices for the stannides. Spin reorientation occurs in all neodymium- containing samples in which the easy magnetization direction cants away from the c-axis and the a-axis with increasing temperature for the germanides and the stannides, respectively. The easy magnetization direction of all samarium-containing samples is parallel to, or at least aligned at a small angle with, the basal plane of the unit cell at room temperature. An analysis of the Mn-Mn interatomic distances in RMn6X6 and RMn6-xFexX6, where R is a rare earth and X is germanium or tin, indicates that there is a critical Mn-Mn distance, dT ≈ 2.6145 Å, below and above which the coupling within the manganese sublattice is anti ferromagnetic and ferromagnetic, respectively\"--Abstract, page iv.
"],"dc:identifier":["https://scholarsmine.mst.edu/doctoral_dissertations/1364"],"dc:subject":["Chemistry"],"dc:title":["The atomic and magnetic structures of several iron-substituted rare-earth manganese germanides and stannides"],"dc:type":["Dissertation - Restricted Access"],"thesis:degree_name":["Ph. D. in Chemistry"],"thesis:institution_name":["University of Missouri--Rolla"]},"updated_at":"2026-07-24T03:19:38Z"}