Weakly coupled triplet pair states probed by quantum beating in delayed fluorescence in tetracene crystals

被引：13

作者：

Wang, Zhiwei ^{[1
,2
]}

Zhang, Chunfeng ^{[1
,2
]}

Wang, Rui ^{[1
,2
]}

Wang, Guodong ^{[1
,2
]}

Wang, Xiaoyong ^{[1
,2
]}

Xiao, Min ^{[1
,2
,3
]}

机构：

[1] Nanjing Univ, Sch Phys, Natl Lab Solid State Microstruct, Nanjing 210093, Jiangsu, Peoples R China

[2] Nanjing Univ, Collaborat Innovat Ctr Adv Microstruct, Nanjing 210093, Jiangsu, Peoples R China

[3] Univ Arkansas, Dept Phys, Fayetteville, AR 72701 USA

来源：

JOURNAL OF CHEMICAL PHYSICS | 2019年 / 151卷 / 13期

基金：

国家重点研发计划; 中国国家自然科学基金;

关键词：

SINGLET-EXCITON-FISSION; CHARGE-TRANSFER; DECAY DYNAMICS; PENTACENE; EFFICIENCY; COHERENT; INTERMEDIATE; 100-PERCENT; DIMERS; LIMIT;

D O I：

10.1063/1.5110188

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The intermediate state of a correlated triplet pair [(1)(TT)] is pivotal for understanding the mechanism of the singlet fission process in molecule systems. Recently, a spatially separated state of a triplet pair [(1)(TMIDLINE HORIZONTAL ELLIPSIST)] has been proposed to drive the dissociation of exchange-coupled (1)(TT) into free triplets. Here, we study the correlated triplet pairs by monitoring quantum beats in delayed fluorescence from tetracene crystals upon applying magnetic fields of different amplitudes and alignments. We argue that the triplet pairs probed by the quantum beat spectrum are weakly coupled, i.e., the spatially separated (1)(TMIDLINE HORIZONTAL ELLIPSIST) state. The experimental data suggest the existence of a direct channel of S-1 -> (1)(TMIDLINE HORIZONTAL ELLIPSIST) in addition to the widely accepted channel of S-1 -> (1)(TT) -> (1)(TMIDLINE HORIZONTAL ELLIPSIST) for singlet fission. Our work suggests that the quantum beat spectrum is a useful tool to directly probe the (1)(TMIDLINE HORIZONTAL ELLIPSIST) state which is valuable for elucidating the intrinsic mechanism of singlet fission.

引用

页数：8

共 88 条

[1]

Bakulin AA, 2016, NAT CHEM, V8, P16, DOI [10.1038/NCHEM.2371, 10.1038/nchem.2371]

[2] Evidence for Charge-Transfer Mediation in the Primary Events of Singlet Fission in a Weakly Coupled Pentacene Dimer [J].