Evidence for the phantom state in photoinduced cis– trans isomerization of stilbene

• Published in: Chemical physics letters Vol. 493; no. 4; pp. 255 - 258
• Main Authors: Kovalenko, S.A., Dobryakov, A.L., Ioffe, I., Ernsting, N.P.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.06.2010
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2010.05.022

[Display omitted] ► The intermediate phantom state is revealed in the course of cis-trans isomerization of stilbene, with its lifetime to be 0.4 ps in acetonitrile and 0.3 ps in hexane. Transient absorption spectra of cis-stilbene in solution, recorded in the range 275–690 nm with 80 fs instrument response, reveal two successive evolving bands. One at 630 nm decays on a subpicosecond scale; it corresponds to vertically-excited nearly planar S 1 state. The other, growing and decaying band at 340 nm, is shown to be consistent with theoretically predicted phantom state p∗ of perpendicular molecular geometry. The lifetime of p∗ is determined to be τ p ∗ = 0.4 ps in acetonitrile and 0.3 ps in hexane.