Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Inverted solvatochromism

Although inverted solvatochromism in betaines has been widely studied, no test clearly exposing the abmpt change from bathochromic solvatochromism to hyp-sochromic solvatochromism has so far been devised. Finding that the dipolarity of 1-chlorobutane increases markedly with decreasing temperature" allowed us to unambiguously expose this solvatochromic change" (see Fig. 9.3.13). [Pg.619]

An interesting situation is encountered in the analysis of electronic transitions that results from chromophores which, assisted by solvent polarity, can undergo a change in the electronic state responsible for the fluorescence emission this is a frequent occurrence in systems involving a TICT mechanism. In this situation, a plot of Stokes shift against solvent polarity is a bilinear curve depending on whether the solvents are non-polar (where the fluorescence is emitted from the normal excited state of the chromophore) or polar enough for the transition to take place from the more polar state. Unless the solvents used are carefully selected, it is venturesome to assume that the electronic states will be inverted simply because the variation of solvatochromism with a function of solvent polarity is bilinear. [Pg.610]

Engberts et al. originally proposed that the appearance of a hexagonal phase transition correlated to the inverted hexagonal phase (Hn), which is often observed for two-tailed surfactants and cationic lipids mixed with DOPE. Further investigations using a solvatochromic fluorophore, Nile Red, revealed the formation of the normal hexagonal phase In this experiment, the results were compared... [Pg.3331]


See other pages where Inverted solvatochromism is mentioned: [Pg.344]    [Pg.344]    [Pg.144]    [Pg.701]    [Pg.344]    [Pg.344]    [Pg.144]    [Pg.701]    [Pg.162]    [Pg.199]    [Pg.400]    [Pg.223]    [Pg.199]    [Pg.609]   
See also in sourсe #XX -- [ Pg.619 ]




SEARCH



Inverted

Inverter

Invertibility

Invertible

Inverting

Solvatochromic

Solvatochromicity

Solvatochromism

Solvatochromisms

© 2024 chempedia.info