排序方式: 共有20条查询结果,搜索用时 69 毫秒
1.
2.
Dmitry V. Peryshkov 《Journal of fluorine chemistry》2010,131(11):1252-1256
The anhydrous salt K2B12F12 crystallized from aqueous solution and its structure was determined by single crystal X-ray diffraction. The Ni2In-type structure it exhibits is rare for an A2X ionic compound at 25 °C and 1 atm., consisting of an expanded hexagonal close-packed array of B12F122− centroids (cent?cent distances: 7.204-8.236 Å) with half of the K+ ions filling all of the Oh holes and half of the K+ ions filling all of the D3h trigonal holes in the close-packed layers that are midway between two “empty” Td holes. The structure is also unusual in that the bond-valence sum for the K+ ions in Oh holes is less than or equal to 0.73 (the bond-valence sum for the other type of K+ ion is 1.16). A variation of the Ni2In structure is exhibited by the previously published monohydrate Cs2(H2O)B12F12, for which an improved structure is also reported here. For K2B12F12: monoclinic, C2/c, a = 8.2072(8), b = 14.2818(7), c = 11.3441(9) Å, β = 92.832(5)°, Z = 4, T = 120(2) K. For Cs2(H2O)B12F12: orthorhombic, P212121, a = 9.7475(4), b = 10.2579(4), c = 15.0549(5) Å, Z = 4, T = 110(1) K. 相似文献
3.
Shustova NB Kuvychko IV Peryshkov DV Whitaker JB Larson BW Chen YS Dunsch L Seppelt K Popov AA Strauss SH Boltalina OV 《Chemical communications (Cambridge, England)》2011,47(3):875-877
High-temperature syntheses of the new C(60)(i-C(3)F(7))(2,4,6) and C(70)(i-C(3)F(7))(2,4) isomers and their characterization by spectroscopic methods, X-ray crystallography, cyclic voltammetry and density functional theory provide compelling evidence that they are superior electron acceptors than trifluoromethylfullerenes. 相似文献
4.
L. Seetha Lakshmi V Sridharan DV Natarajan V Sankara Sastry T S Radhakrishnan 《Pramana》2002,58(5-6):1019-1026
Mn site is substituted with closed shell ions (Al, Ga, Ti, Zr and a certain combination of Zr and Al) and also with Fe and
Ru ions carrying the magnetic moment (S=5/2 and 2 respectively) at a fixed concentration of 5 at %. Substitution did not change either the crystal symmetry or the
oxygen stoichiometry. All substituents were found to suppress both the metal-insulator and ferromagnetic transition temperatures
(T
p(ρ) and T
C, respectively) to varied extents. Two main contributions identified for the suppression are the lattice disorder arising
due to difference in the ionic radii between the substituent (r
M) and the Mn3+ ion (r
Mn
3+) and in the case of the substituents carrying a magnetic moment, the type of magnetic coupling between the substituent and
that of the neighboring Mn ion. 相似文献
5.
6.
Dmitry V. Peryshkov Zoran Mazej Steven H. Strauss 《Journal of fluorine chemistry》2010,131(11):1225-1228
Crystals grown from anhydrous HF solutions of CsAsF6 and Cs2B12F12 or KAsF6 and Cs2B12F12 are shown by Raman spectroscopy and single-crystal X-ray diffraction to be the ternary salts K3(AsF6)(B12F12) or Cs3(AsF6)(B12F12). Both compounds exhibit a modified version of the anti-perovskite structure. They are rare examples of crystals that simultaneously contain octahedral and icosahedral molecular species and are also rare examples of salts containing fluoroanions with different shapes and charges. The crystallographic results show that both compounds are densely packed. 相似文献
7.
Kareev IE Shustova NB Peryshkov DV Lebedkin SF Miller SM Anderson OP Popov AA Boltalina OV Strauss SH 《Chemical communications (Cambridge, England)》2007,(16):1650-1652
The title compound, prepared from C(60) and CF(3)I at 500 degrees C, exhibits an unusual fullerene(X)12 addition pattern that is 40 kJ mol(-1) less stable than the previously reported C(60)(CF(3))12 isomer. 相似文献
8.
Reaction of a boryl hydride pincer complex (POBOP)Ru(H)(PPh3) (POBOP?=?1,7-OP(i-Pr)2-m-2-carboranyl) and BH3(SMe2) at 70?°C led to the selective formation of a pincer-supported metallaborane (POBOP)Ru(B3H8). Single crystal structure of (POBOP)Ru(B3H8) was determined. This complex features coordination of the carborane cluster through adjacent boryl and borane groups that impose significantly different trans-influence on the coordinated B3H8 fragment. 相似文献
9.
10.