In the last decade, one of the most widely examined compounds of motal-organic frameworks was undoubtedly ((CH)NH)(Zn(HCOO)), but the problem of the importance of framework dynamics in the order-disorder phase change of the mechanism has not been fully clarified. In this study, a combination of temperature-dependent dielectric, calorimetric, IR, and Raman measurements was used to study the impact of ((CH)NH)(Zn(DCOO)) formate deuteration on the phase transition mechanism in this compound. This deuteration led to the stiffening of the metal-formate framework, which in turn caused an increase in the phase transition temperature by about 5 K.
View Article and Find Full Text PDFNovel heterometallic formate [(CH3)2NH2][Fe(III)Mg(II)(HCOO)6] (DMFeMg) was prepared and characterized by single crystal X-ray diffraction, DSC, dielectric, magnetic susceptibility, Raman and IR methods. We also report thermal, Raman and IR studies of the known compound [(CH3)2NH2][Fe(III)Fe(II)(HCOO)6] (DMFeFe). DMFeMg crystallizes in the niccolite structure (P3[combining macron]1c space group).
View Article and Find Full Text PDFA novel formate [(CH3)2NH2][Na0.5Cr0.5(HCOO)3] (DMNaCr) was prepared by a solvothermal method.
View Article and Find Full Text PDFWe report the synthesis, crystal structure, thermal, dielectric, Raman, infrared, and magnetic properties of [(CH3)2NH2][Na(0.5)Fe(0.5)(HCOO)3] (DMNaFe), the first metal formate framework templated by organic cations, presenting an ABO3 perovskite architecture with NaO6 octahedra as building blocks of the framework.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
May 2011
We present dielectric spectroscopy data obtained for gallium-doped Cd(0.99)Mn(0.01)Te:Ga mixed crystals, which exhibit a very special case of the two-power-law relaxation pattern with the high-frequency power-law exponent equal to 1.
View Article and Find Full Text PDFJ Phys Condens Matter
March 2010
In this paper the complex dielectric permittivity of gallium doped Cd(0.99)Mn(0.01)Te mixed crystals is studied at different temperatures.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
April 2010
In this paper, we propose a transparent subordination approach to anomalous diffusion processes underlying the nonexponential relaxation. We investigate properties of a coupled continuous-time random walk that follows from modeling the occurrence of jumps with compound counting processes. As a result, two different diffusion processes corresponding to over- and undershooting operational times, respectively, have been found.
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