Donor-acceptor transfer compounds photochemistry

The soliton concept is likely to prove fruitful in many aspects of photochemistry especially where organized systems are involved, It has been proposed that charge transfer excitons in mixed-stack donor-acceptor compounds exist in a variety of solitonic states . In this effect charge transfer states couple to lattice phonons in the crystal lattice to form the comparatively stable solitons. 

Some references of reviews besides the ones already cited are given [1,3, 5-9, 19, 23-25, 28, 31, 33]. Organometallic photochemistry [36] was excellently treated in [37] and may be compared with inorganic photochemistry to gain further inspiration [38-40]. A recent multiauthored book strongly overlaps with the subject matter of the present section, and should certainly be consulted [41]. Electron transfer reactions play a determinant role in many photocatalytic processes several recent reviews and books may be cited on this topic [42-44]. The photochemistry of the M-CO bond [45] and the theme of photocatalysis by transition metal complexes [46] have recently been reviewed. Covalently linked donor-acceptor systems for mimicry of photosynthetic energy transfer have been discussed in [47]. Several special issues of Coordination Chemistry Reviews have been devoted to the photochemistry and photophysics of coordination compounds [48-50], and a special issue to photochemistry [51]. Further developments in photochemistry were the subject of a special issue of Chemical Reviews [52]. Practical considerations useful for designing photochemical experiments may be found in [53]. 

Aral et al. investigated the photochemistry of the linear shaped aromatic enediynes (186) and (187). The quantum yield of both ( )- (Z) and (Z) ( ) isomerizations considerably decreased in (186) and (187) because of an increase in the number of photochemical processes that yielded nonfluorescent excited species. The compound (188) showed characteristic charge-transfer absorption due to the strong donor-acceptor chromo-phores. The enediynes (189) on Au nanoparticles underwent Bergman-type cyclization leading to a polymerized coating via biradical intermediates. 

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