Origin of Color

The colors of iron oxides are eaused by at least two of these electron transitions (1 and 2) as illustrated for the speetmm of goethite (Fig. 3-1). 

More detailed information on the physical causes of color can be obtained from books by Nassau (1983) and Bums (1993). 

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Benitoite is a rare, strongly dichroic, blue mineral used as a gemstone. In spite of much effort in its study, the origin of color in benitoite has not been definitively estabhshed. Because traces of Fe are found, ideas proposed include the Fe -Ti or the Fe -Fe inter-valance charge transfer. While most benitoite is colorless when viewed down the c-axis, there are a very small number of exceedingly rare stones, which are pink in this direction (Rossman 1988). 

Chapter 8 (which can be covered before Chapter 7 if desired) provides a very broad overview of molecular spectroscopy and the origins of color. The topics range all the way from rainbows and peacock feathers to microwave ovens and the greenhouse effect. Once again, the emphasis is on obtaining an understanding of how we know what we know about molecules, with mathematics kept to a minimum in most sections. 

Nassau, K. (1978) The origins of color in minerals. Amer. Mineral., 63, 219-29. Rossman, G. R. (1988) Optical spectroscopy. In Spectroscopic Methods in... 

Nassau, K. (1978) The origins of color in minerals. Amer. Mineral., 63,219-29. 

ORIGIN OF COLOR IN TRANSITION METAL COORDINATION COMPLEXES4... 

Describe the crystal field theory of bonding in coordination compounds Explain the origin of color in complex species Use the spectrochemical series to explain colors of a series of complexes... 

F centers in crystals in Section 11.9, and the origins of color in glass in Section 21.8 we will discuss color more in Chapter 36. 

Nassau, K. (Ed.) (1998) Color for Science, Art and Technology, Elsevier, Amsterdam. A collection of articles describing the origins of color in gemstones. 

Crystal field theory can satisfactorily explain the origin of color in and magnetic properties of octahedral, tetrahedral, and sqnare-planar complexes. 

The origin of color lies in the denominator of (1.17), which predicts an absorbance maximum for a sol, when... 

Now that we understand the origin of color in organic compounds, we are finally able to explore how bleaches function. Most bleaching agents react with conjugated -ir systems, disrupting the extended conjugation ... 

Urones-Garrote E, Lopez AJ, Ramil A, Otero-Waz LC (2011) Microstructur2d study of the origin of color in Rosa Porrino granite and laser cleaning effects. Appl Phys A 104(1) 95-101. 

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