Photoinduced Neutral-to-Ionic Phase Transition in Tetrathiafulvalene-p-chloranil Studied by Time-Resolved Vibrational Spectroscopy

被引：20

作者：

Matsubara, Yoshitaka ^{[1
]}

Okimoto, Yoichi ^{[1
]}

Yoshida, Tatsushi ^{[1
]}

Ishikawa, Tadahiko ^{[1
]}

Koshihara, Shin-ya ^{[1
,2
]}

Onda, Ken ^{[3
]}

机构：

[1] Tokyo Inst Technol, Dept Chem & Mat Sci, Meguro Ku, Tokyo 1528551, Japan

[2] Japan Sci & Technol Agcy JST, CREST, Kawaguchi, Saitama 3320012, Japan

[3] Tokyo Inst Technol, Dept Environm Chem & Engn, Yokohama, Kanagawa 2268502, Japan

来源：

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN | 2011年 / 80卷 / 12期

关键词：

photoinduced phase transition; femtosecond pump-probe spectroscopy; infrared vibrational spectroscopy; neutral-ionic phase transition; organic charge transfer complex; CHARGE-TRANSFER COMPLEXES; TTF-CA; TRANSFER CRYSTAL; SPECTROMETER; DYNAMICS; ORDER; RAMAN; BAND;

D O I：

10.1143/JPSJ.80.124711

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We studied the photoinduced neutral-to-ionic phase transition in tetrathiafulvalene-p-chloranil (TTF-CA) using time-resolved infrared (IR) vibrational spectroscopy with a broadband femtosecond IR laser pulse and a linear IR detector array. After photoexcitation, the strength of the TTF a(g)upsilon(3) band increased, indicating that dimerization is activated within similar to 1 ps. In contrast, the strength of the CAb(1u)upsilon(10) band, whose frequency is proportional to the degree of charge transfer (rho), decreased, and a broad weak band appeared in the lower-frequency region. This implies that large fluctuations in charge transfer continued until about 20 ps after the photoexcitation. These results indicate a large difference between the electronic structures of the ionic phases generated by thermalexcitation and photoexcitation, although a dimerized structure was observed in both cases.

引用

页数：5