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Crystallization of Monoclinic 2TiO 2 ·5Nb 2 O 5
Author(s) -
Yamaguchi Osamu,
Tomihisa Daijo,
Ogiso Nobuyuki,
Shimizu Kiyoshi
Publication year - 1986
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1986.tb04805.x
Subject(s) - monoclinic crystal system , orthorhombic crystal system , crystallization , crystallography , activation energy , materials science , niobium , amorphous solid , mineralogy , chemistry , crystal structure , metallurgy , organic chemistry
Monoclinic 2TiO 2 ·5Nb 2 O 5 crystallizes at 810° to 835°C from an amorphous material prepared by the simultaneous hydrolysis of titanium and niobium alkoxides. Crystallization isotherms are described by the contracting cube equation 1 − (1 − f) 113 = k(t − t 0 ); the activation energy is 315 kJ·mol −1 . Monoclinic 2TiO 2 ·5Nb 2 O 5 transforms to the orthorhombic modification at ∼1200° to 1300°C.