Chalcogen, H-N-O-Se, N-x polyhedra, Phase transitions

• H-N-O-Se-Te
• H-N-Na-O-Se
• C-H-N-O-Se-U
• Cu-H-N-O-Se
• structural transitions
• temperature for structural transition
• fusion
• temperature for congruent melting
• pressure for structural transition
• pnictogen
• chalcogen
• non-disordered
• tetraoxoselenate
• quaternary
• monoclinic
• triclinic
• orthorhombic
• trigonal
• hexagonal