Optical properties ionic compounds

Since the X-ray diffraction studies of Zintl et al. , these members of the family of intermetallic compounds have been of special interest because some of their chemical properties are unusual for intermetallic phases. Many experimental investigations have been reported for binary and ternary B32 type compounds. Besides the crystal structure " , the thermodynamic behavior , electrical conductivity ", magnetic susceptibility , NMR data elastic constants - and optical properties have been studied. Additionally for LiAl electrochemical investigations have been performed in view of the recent interest in fast ionic conductors " . ... 

Many carbides and silicides of composition AX are formed by transition metals. These carbides and silicides are characterized by very high melting points, extreme hardness, optical opacity and relatively high electrical conductivity. Many of them have the sodium chloride structure but they are not ionic compounds rather do they resemble the corresponding nitrides and phosphides in simulating alloy systems in many of their properties. For this reason they will be discussed later. 

One of the most widely used photo-chemicals for pH measmement is fluorescein [6], which displays complex optical properties dependent upon its ionic form (See Chap. 4, compound 4.3). In particular only the two anionic forms present at high pH are fluorescent. Fluorescein can be used a wavelength ratiometric probe... 

The convenience of working with miCToemnlsions is based on their properties thermodynamic stability, optical transparency, and easy preparation that make possible to quantitate drugs of different hydrophobicity, both nentral and ionic compounds in the same run. 

Crystal elastic constants, 12-33 to 38 Crystal ionic radii, 12-11 to 12 Crystal lattice energy, 12-19 to 31,12-32 Crystal optical properties elements, 12-121 to 145 inorganic compounds, 10-246 to 249 minerals, 4-149 to 155 various materials, 12-146 to 164 Crystal structure... 

On the other hand, fluorine s high electronegativity and its ability to form mostly ionic chemical bonds, provide materials with several useful properties. First, compared to oxides, fluoride compounds have a wide forbidden zone and as a result, have low electroconductivity. In addition, fluorides are characterized by a high transparency in a wide optical range that allows for their application in the manufacturing of electro-optical devices that operate in the UV region [42,43]. 

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