Model of Heat Capacity in Volume Dimension.

Heat capacity is an important and fundamental thermodynamic parameter in materials. The temperature-dependent heat capacity (HC) was studied extensively. Here, the universal correlation between the experimental heat capacity and the coefficient of thermal expansion β in reference solids at high temperatures: = + β ( and : constants) and the volume-dependent heat capacity in the temperature range from several Kelvins to melting temperatures is quantitatively determined: = β, and a new phenomenological model of the experimental heat capacity below the melting temperature in the volume dimension is established: = + (the non-volume-dependent heat capacity = , : Debye function).

Epitaxial Growth of Orthorhombic GaFeO₃ Thin Films on SrTiO₃ (111) Substrates by Simple Sol-Gel Method.

A Sol-gel method assisted with spin-coating has been successfully used to grow orthorhombic GaFeO₃ epitaxial films on SrTiO₃ (111) substrates for the first time. The film with crystal structure has been grown along the c-axis. The rocking curve of (004) reflection shows that the Full-Width at Half-Maximum (FWHM) value could be determined to be 0.

Study on Upconversion and Thermal Properties of Tm/Yb Co-Doped La₂O₃-Nb₂O₅-Ta₂O₅ Glasses.

The effect of Yb ions on upconversion luminescence and thermal properties of Tm/Yb co-doped La₂O₃-Nb₂O₅-Ta₂O₅ glasses has been studied. Glass transition temperature is around 740 °C, indicating high thermal stability. The effect of Yb ions on the thermal stability is not obvious.

Low-melting imidazolium-based salts with the paramagnetic reineckate-analogue anion [Cr(NCS)4(bipy)]- (bipy = 2,2'-bipyridine): syntheses, properties, and structures.

In order to investigate the potential ionic liquid properties of Reineckate-analogue materials, four new salts, consisting of the heteroleptic [Cr(NCS)(4)(bipy)](-) complex anion and imidazolium-based cations A(+) = 1-ethyl-3-methylimidazolium, 1-n-butyl-3-methylimidazolium, pentamethylimidazolium, and 1,3-dimethyl-2,4,5-triphenylimidazolium, were investigated. Their structures were established by single-crystal X-ray diffraction. The compounds are paramagnetic with effective magnetic moments in the range of those expected by the number of unpaired spins of the chromium(III) ion.

Two isotypic transition metal germanophosphates M(II)4(H2O)4[Ge(OH)2(HPO4)2(PO4)2] (M(II) = Fe, Co): synthesis, structure, Mössbauer spectroscopy, and magnetic properties.

Synthetic, structural, thermogravimetric, Mössbauer spectroscopic, and magnetic studies were performed on two new isotypic germanophosphates, M(II)(4)(H(2)O)(4)[Ge(OH)(2)(HPO(4))(2)(PO(4))(2)] (M(II) = Fe, Co), which have been prepared under hydro-/solvo-thermal conditions. Their crystal structures, determined from single crystal data, are built from zigzag chains of M(II)O(6)-octahedra sharing either trans or skew edges interconnected by [GeP(4)O(14)(OH)(4)](8-) germanophosphate pentamers to form three-dimensional neutral framework structure. The edge-sharing M(II)O(6)-octahedral chains lead to interesting magnetic properties.

Chemical bonding and properties of "layered" quaternary antimonide oxide REOZnSb (RE = La, Ce, Pr, Nd).

An efficient route to construct a three-dimensional crystal structure is stacking of two-dimensional building blocks (2D-BBs). The crystal structures of potential thermoelectric compounds REOZnSb (RE = La, Ce, Pr, Nd) were virtually constructed from insulating [REO] and conducting [ZnSb] layers. Further optimizations performed by means of first-principles calculations show that REOZnSb should exhibit semimetal or narrow band-gap semiconductor behaviors, which is a prerequisite for high thermoelectric efficiency.

Thermoelectric properties of Eu(Zn(1-x)Cd(x))2Sb2.

The thermoelectric performance of EuZn(2)Sb(2) and EuCd(2)Sb(2) was optimized by mixed occupation of the transition metal position. Samples in the solid solution Eu(Zn(1-x)Cd(x))(2)Sb(2) with the CaAl(2)Si(2)-type crystal structure (space group Pm1) were prepared from the elements for compositions with x = 0, 0.1, 0.

A new type of thermoelectric material, EuZn2Sb2.

Polycrystalline EuZn(2)Sb(2) is prepared by direct reaction of the elements. Its composition, structure, magnetism, heat capacity, and thermoelectric properties have been investigated. EuZn(2)Sb(2) crystallizes in p3m space group with a=4.