Structure dependence of the low-lying excited states and the first dipole hyperpolarizability of phenol blue

✍ Scribed by Agostinho Serrano; Sylvio Canuto

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 295 KB
• Volume: 70
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/(sici)1097-461x(1998)70:4/5<745::aid-qua20>3.0.co;2-#

✦ Synopsis

between the two extreme conformations of a keto and an eno form. The keto form is more stable in the gas phase and the eno form is believed to be more stable in solution. We show that the keto form can prevail in nonpolar solvents, but in polar solvents like chloroform, the eno form should be dominant. Analysis is made of the solvent effects in the low-lying absorption transition and its consequence in the first dipole hyperpolarizability. We show by explicit calculations that the hyperpolarizability of the eno form is one order of magnitude greater than in the keto form. We then contend that this structure dependence may also lead to very large changes of the hyperpolarizability of similar molecules and polymers in solvents.