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A series of iron-doped KTiOPO4 (KTP: Fe) single crystals in which iron substitutes for 0.1–0.3% titanium was grown. The structure of the KTP: Fe crystals was determined, and their dielectric and conducting properties were studied. An X-ray diffraction analysis failed to reveal such asmall amount of Fe+3 ions in titanium octahedral positions of the structure. It was found that an increase in the iron concentration results in a lowering of the symmetry of Ti(1)O6 and Ti(2)O6 octahedra. The splitting of the dielectric anomaly due to the ferroelectric phase transition was explained by the mechanism of incorporation of an impurity into different growth pyramids of the crystals. It was established that the aging of the KTP: Fe crystals leads to changes in the permittivity and electrical conductivity during long storage.  相似文献   
2.
Russian Journal of General Chemistry - Tetraphenylantimony methacrylate Ph4SbO2CC(CH3)=CH2 and tetraphenylantimony crotonate Ph4SbO2CCH=CHCH3 were synthesized by the action of acids on Ph5Sb or on...  相似文献   
3.
Crystallography Reports - The bis[(2E)-3-phenylprop-2-enoate]-tris(п-tolyl)antimony n-Tol3Sb[OC(O)CH=CHPh]2 complex is obtained as a result of interaction of tri-n-tolylantimony, hydrogen...  相似文献   
4.
Simple crystal forms are analyzed as the orbits of point symmetry groups on a set of crystal planes of space. All known polyhedra are described and structurized based on the theory of the orbits of groups, which provided a new, more harmonious approach to this problem. The orbits of groups can be general or particular and characteristic or non-characteristic. All possible versions of all crystallographic groups are listed in the table. The problem of the equivalence of polyhedra as the orbits of point symmetry groups is considered. An analysis of this problem has shown that 32 point crystallographic symmetry groups correspond to 139 symmetrically nonequivalent polyhedra.  相似文献   
5.
Crystallography Reports - A new germanate phase, grown in the Li2O · MoO3–CaO–GeO2 pseudoternary system with addition of Cr2O3, has been studied by X-ray diffraction. The...  相似文献   
6.
The reactions of the title compound, Me2Sn(S-SO3Na · H2O)2, with alkyliodides and trimethyltin chloride in an aqueous medium, as well as with dibenzo-18-crown-6 (DB-18-C-6) in acetone have been studied. The iodides RI (R = Me, Et) attack both of the tin—sulfur bonds to give dimethyltin diiodide and the respective disulfides, R2S2. Trimethyltin chloride enters an exchange reaction which involves sodium ions and affords Me2Sn(S-SO3SnMe3)2 as the reaction intermediate; the latter decomposes to ultimately give trimethyltin sulfate, dimethyltin thiosulfite, and elemental sulfur. An ionic complex, [Me2Sn(S-SO3)2]2 2–[Na(DB-18-C-6)(Me2CO)]+[Na(DB-18-C-6)(Me2CO)(H2O)]+, soluble in acetone and methylene chloride has been also synthesized, and its structure has been determined by means of X-ray techniques.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 962–966, May, 1993.  相似文献   
7.
Simple crystal forms are analyzed as the orbits of noncrystallographic point symmetry groups on a set of smooth or structured (“hatched”) planes of crystal space. Polyhedra with symmetrically equivalent faces, obtained using noncrystallographic point symmetry groups, are considered. All possible versions of simple forms for all noncrystallographic groups are listed in a unified table.  相似文献   
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