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Effect of an External Electric Field on Polytypic Growth of CdI 2 Crystals from Solutions
Author(s) -
Pałosz B.,
Przedmojski J.
Publication year - 1982
Publication title -
crystal research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.377
H-Index - 64
eISSN - 1521-4079
pISSN - 0232-1300
DOI - 10.1002/crat.2170171209
Subject(s) - electric field , trigonal crystal system , hexagonal crystal system , crystallography , crystallization , field (mathematics) , perpendicular , materials science , chemistry , analytical chemistry (journal) , crystal structure , physics , geometry , mathematics , organic chemistry , chromatography , quantum mechanics , pure mathematics
The effect of an external steady electric field on polytypic growth of CdI 2 crystals was investigated. Crystals were grown at four temperatures: 5, 25, 35, and 50°C with the use of four solvents: H 2 O, C 2 H 5 OH, 3 H 2 O + 1 C 2 H 5 OH and 1 H 2 O + 1 C 2 H 5 OH. The electric field of the intensity 500 to 2500 V/cm was oriented in two directions: perpendicular or parallel to the c‐axis of hexagonal plates of CdI 2 crystals. The analysis of the effect of the field on polytypism of CdI 2 was based on the analysis of the structure of about 800 crystals grown in the presence of electric field and of about 1000 crystals grown in neutral conditions. It was established that the weak electric field used for crystallization of CdI 2 does not influence noticeably the relative stability of basic polytypes (2H, 4H) and of complex polytypic structures (ordered and disordered). The electric field may influence the structure of CdI 2 crystals in two ways: (i) the polytypes formed in the presence of the field have on average two times larger cells than the polytypes formed in neutral conditions, (ii) the polytypes formed in neutral conditions have usually hexagonal cells; only 6 to 30% of polytypes are of rhombohedral type. When the electric field was used the percentage of rhombohedral polytypes increased to about 65%.