Photo-illumination effects have been measured for the compound [Co III-LS(tmpda)(3,6-DBSQ)(3,6-DBCat)]. When the aforementioned compound was illuminated at 5K, the magnetization value increased from μeff=1.87 to 2.03 μB. The absorption spectra after illumination show that the absorption band at around 730 nm, which is characteristic of the [CoII-HS(tmpda)(3,6-DBSQ)2] state, increased in intensity and that the charge transfer band from 3,6-DBCat to 3,6-DBSQ at 2500 nm was reduced in intensity. IR spectra show that the C-O stretching peak at 1279cm-1 is decreased in intensity. These results confirm that a photo-induced intra-molecular electron transfer, [Co III-LS(tmpda)(3,6-DBSQ)(3,6-DBCat)]→[CoII-HS(tmpda) (3,6-DBSQ)2], was induced. The lifetime of the metastable state at 5 K was 15min. Furthermore, it was found that reverse valence tautomerism can be induced by exciting the CoII-HS to 3,6-DBSQ charge transfer band in metastable [CoII-HS(tmpda)(3,6-DBSQ)2].
All Science Journal Classification (ASJC) codes
- Materials Science(all)