Vanadium thermodynamic propertie

V.N. Yeremenko, G.M. Lukashenko, V.R. Sidorko. Thermodynamic properties of vanadium, chromium and manganese silicides at elevated temperatures // Rev.Intern. Haut.Temp.Refract.- 1975.- V.12, No.3.- P.237-240. 

Veleckis, E. and Edwards, R.K., Thermodynamic properties in the systems vanadium-hydrogen, niobium-hydrogen, and tantalum-hydrogen. Journal of Physical... 

D. Nicholls, Coordination Chem. Rev., 1966, X, 379 (extensive review on the coordination chemistry of vanadium compounds) J. 0. Hill, I. G. Worsley and L. G. Hepler, Chem. Rev., 1971, 71, 127 (thermodynamic properties and oxidation potentials). 

The constitution of many ferritic steels includes chromium and vanadium as basic alloying elements. Knowledge of the phase diagram and thermodynamic properties of the Cr-Fe-V system is essential to imder-stand the behavior of such iron-based alloys. 

Physical and Chemical Properties. Titanium dioxide [13463-67-7] occurs in nature in three crystalline forms anatase [1317-70-0] brookite [12188-41 -9] and mtile [1317-80-2]. These crystals are essentially pure titanium dioxide but contain small amounts of impurities, such as iron, chromium, or vanadium, which darken them. Rutile is the thermodynamically stable form at all temperatures and is one of the two most important ores of titanium. 

A ubiquitous characteristic of vanadium chemistry is the fact that vanadium and many of its complexes readily enter into redox reactions. Adjustment of pH, concentration, and even temperature have often been employed in order to extend or maintain system integrity of a specific oxidation state. On the other hand, deliberate attempts to use redox properties, particularly in catalytic reactions, have been highly successful. Vanadium redox has also been successfully utilized in development of a redox battery. This battery employs the V(V)/V(IV) and V(III)AT(II) redox couples in 2.5 M sulfuric acid as the positive and negative half-cell electrolytes, respectively. Scheme 12.2 gives a representation of the battery. The vanadium components in both redox cells are prepared from vanadium pentoxide. There are two charge-discharge reactions occurring in the vanadium redox cells, as indicated in Equation 12.1 and Equation 12.2. The thermodynamics of the redox reactions involved have been extensively studied [8],... 

Scholtens, B.B., R. Polder, and G.H.J. Broers. 1978. Some thermodynamic, electrical, and electrochemical properties of silver vanadium bronzes. Electrochim. Acta. 23 483 188. 

Crystal field theory is one of several chemical bonding models and one that is applicable solely to the transition metal and lanthanide elements. The theory, which utilizes thermodynamic data obtained from absorption bands in the visible and near-infrared regions of the electromagnetic spectrum, has met with widespread applications and successful interpretations of diverse physical and chemical properties of elements of the first transition series. These elements comprise scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel and copper. The position of the first transition series in the periodic table is shown in fig. 1.1. Transition elements constitute almost forty weight per cent, or eighteen atom per cent, of the Earth (Appendix 1) and occur in most minerals in the Crust, Mantle and Core. As a result, there are many aspects of transition metal geochemistry that are amenable to interpretation by crystal field theory. 

---