Batochromic shifts

Both the CTC and the bromonium tribromide species have their A-max at 272 nm, but with very different e. Furthermore, at the employed Br2 concentrations the counteranion of the bromonium ion is partitioned between Br3 and Br5 , the latter having its A-max batochromically shifted at 310 nm. The equilibrium constant between the tribromide and the pentabromide species of Scheme 4 is 22.3 M l, that is nearly coincident with that found for the tetrabutylammonium tribromide-pentabromide equilibrium (ref. 22). 

It is evident that the s-cis frozen conformation in the ring of 2 shows a batochromic shift, but a much lower absorption (s) in comparison with butadiene (1). Woodward and... 

A FBrster-type transfer mechanism (48) was proposed to occur. Batochromic shifts and hyperchromicity were observed In the absorption spectra of systems [10b,1,3] and to the largest extent In [10b,2] (44,45). On specific excitation of the benzophenone chromophore, triplet transfer to the naphtalene moiety occurs with 100 percent efficiency. The rate of transfer is greater than lO s l g d not measurably dependent on chain length. Since the ratio of Intersystem crossing in benzophenone is of the order of (49), energy transfer will occur, after inter-... 

Subsequent studies reported by Sanchez del Rio et al. (2004, 2005) did not find either iron in metallic form or goethite in archeological MB. In the most recent literature, it is commonly accepted that MB coloration is mainly due to batochromic shift of the indigo absorption bands as a result of the association of the dye to the inorganic support (Reinen et al., 2004). 

The batochromic effect (or red shift) is a shift to longer wavelengths. 

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