Chalcogen, Nonmetal, Kartashev

• Na-Nb-O
• B-Fe-Gd-Nd-O
• Eu-La-Mn-O-Pb
• F-K-Mo-O-Rb
• Fe-Ge-Na-O
• magnetic properties
• thermal and thermodynamic properties
• magnetic transitions
• temperature for structural transition
• phase transitions
• nonmetal
• transitional
• chalcogen
• oxide
• alkali
• trigonal
• orthorhombic
• cubic
• monoclinic
• tetragonal