Singlet Fission and Excimer Formation in Disordered Solids of Alkyl-Substituted 1,3-Diphenylisobenzofurans
JOURNAL OF PHYSICAL CHEMISTRY A, cilt.121, sa.45, ss.8596-8603, 2017 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 121 Sayı: 45
- Basım Tarihi: 2017
- Doi Numarası: 10.1021/acs.jpca.7b07362
- Dergi Adı: JOURNAL OF PHYSICAL CHEMISTRY A
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.8596-8603
- Orta Doğu Teknik Üniversitesi Adresli: Hayır
Özet
We describe the preparation and excited state dynamics of three alkyl derivatives of 1,3-diphenylisobenzofuran (1) in both solutions and thin films. The substitutions are intended to disrupt the slip-stacked packing observed in crystals of 1 while maintaining the favorable energies of singlet and triplet for singlet fission (SF). All substitutions result in films that are largely amorphous as judged by the absence of strong X-ray diffraction peaks. The films of 1 carrying a methyl in the para position of one phenyl ring undergo SF relatively efficiently (>= 75% triplet yield, (Phi(T)) but more slowly than thin films of 1. When the methyl is replaced with a t-butyl, kinetic competition in the excited state favors excimer formation rather than SF (Phi(T) = 55%). When t-Bu groups are placed in both meta positions of the phenyl substituent, SF is slowed further and Phi(T) = 35%.