E. S. R. Gopal

Equilibrium critical phenomena in binary liquid mixtures

We present a comprehensive and critical review of recent experimental studies of equilibrium critical phenomena in binary liquid mixtures, and show that binary liquid mixtures constitute ideal systems in which to attempt a detailed verification and evaluation of some predictions of the modern theories of critical phenomena. A section on general considerations includes brief descriptions of the recent theoretical predictions regarding critical phenomena. The next three sections (3, 4 and 5) contain detailed and critical surveys of experimental investigations of the coexistence curve, specific heat and thermal expansion in binary liquids. Some comparative discussions of critical phenomena in pure fluids and magnetic systems are included when felt necessary. In section 6, we survey studies of other equilibrium phenomena in binary liquids, especially dielectric constant measurements, interface phenomena and measurements of critical and correction amplitude ratios. Section 7 is devoted to the three major problems which plague experimental investigation of critical phenomena in fluids, namely gravity effects, temperature gradient effects and impurity effects. Some illustrative figures, a comprehensive set of tables summarising recent experimental data, and an extensive list of references have beem provided. In many places in the review we attempt to point out directions in which further experimental and theoretical work would seem to be called for.

Microstructure dependent physical properties of evaporated tin sulfide films

In the field of photovoltaics, semiconductors of the III-V group such as GaAs and InP have been considered as the most efficient absorber materials due to their direct energy band gap and high mobility. In these compounds, arsenic and phosphorus are highly toxic and expensive. In this work we present systematic preparation of low cost SnS thin films and characterize these films to test their suitability for photovoltaic applications. We have observed that the films (with thickness ≅0.5μm) grown at the substrate temperature of 275°C exhibit a low resistive single SnS phase and have a direct optical band gap of 1.35eV with an absorption coefficient of ∼105cm−1. SnS films could be alternative semiconductor materials as absorbers for the fabrication of photovoltaic devices.

Chemical ordering in Ge20Se80−χInχ glasses

Bulk glasses of GeSeIn have been prepared by quenching the melt and have been subjected to thermal crystallization and X-ray structure analysis of devitrified materials. These glasses show a transformation from a single-stage to a double-stage crystallization with respect to composition. The present investigations indicate that these materials are structurally inhomogeneous at a molecular level, in which In2Se3 microclusters are dispersed in the GeSe matrix. These results are discussed using the chemical threshold in glasses.

Influence of annealing on physical properties of evaporated SnS films

The effect of annealing on the composition, crystal structure, surface features and electro-optical properties of tin mono-sulfide (SnS) films, deposited by thermal evaporation at

High pressure clamp for electrical measurements up to 8 GPa and temperature down to 77 K

300^\circ C

Low Resistive Micrometer-Thick SnS : Ag Films for Optoelectronic Applications

, has been studied. Elemental analysis of the films shows sulfur deficiency, which increases at higher annealing temperatures

Thickness Effect on the Physical Properties of Evaporated SnS Films

(T_a)

Structural correlations in GexSe1−x glasses – a neutron diffraction study

. The SnS structure in the as-deposited and annealed films remains orthorhombic. With an increase in

Glass formation in germanium telluride glasses containing metallic additives

Ta_

Review on Tin (II) Sulfide (SnS) Material: Synthesis, Properties, and Applications

, the grain size and the surface roughness are reduced. The electrical resistivity also decreases with increasing