Chalcogen, Trioxoselenate, Phase transitions

• H-Na-O-Se
• Hg-O-Se
• H-Mn-O-Se
• H-K-O-Se
• Fe-H-O-Se
• fusion
• temperature for congruent melting
• decomposition
• decomposition temperature
• structural transitions
• trioxoselenate
• chalcogen
• non-disordered
• transitional
• monoclinic
• orthorhombic
• triclinic
• hexagonal
• trigonal