PMID- 28317965
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20180201
LR  - 20180201
IS  - 1463-9084 (Electronic)
IS  - 1463-9076 (Linking)
VI  - 19
IP  - 13
DP  - 2017 Mar 29
TI  - Direct observation of the rise of delayed fluorescence in 
      dithienylbenzothiadiazole and its role in the excited state dynamics of a 
      donor-acceptor-donor molecule.
PG  - 9118-9127
LID - 10.1039/c7cp00261k [doi]
AB  - Dithienylbenzothiadiazole (DTBT) is used as a building block in several molecules 
      having application in organic light emitting devices (OLED) and organic 
      photovoltaic (OPV) devices. Delayed fluorescence (DF) is the preferred design 
      principle employed currently in OLED research. DTBT has excellent delayed 
      fluorescence properties which makes this moiety a potentially viable OLED 
      material. Here, the dynamics of intersystem crossing (ISC) and reverse 
      intersystem crossing (RISC) have been explored using fluorescence, 
      phosphorescence, fluorescence lifetime and transient absorption measurements. 
      Experimentally it is demonstrated that singlet and triplet states of DTBT are 
      close lying or degenerate and after a certain time the molecules can stay in the 
      singlet or the triplet state forming an equilibrium between the two states which 
      hinders the identification of these two states that could be characterized by 
      routine steady state fluorescence and phosphorescence studies. Similarly in OPV 
      material research, DTBT is coupled with strong donors to form push-pull molecules 
      to produce a prolonged charge separated state. In this study DTBT appended with 
      carbazole at both ends (CDTBT) was used to study the dynamics of DTBT within a 
      donor-acceptor-donor system. The study reveals similar kinds of ISC and RISC in 
      CDTBT along with a competitive deactivation pathway of the singlet state and it 
      was concluded to be through the formation of a charge separated species in CDTBT.
FAU - Mohanty, Maneesha Esther
AU  - Mohanty ME
AUID- ORCID: 0000-0002-9237-0791
AD  - Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, 
      Hyderabad 500 007, India. manee03@gmail.com maneesha@iict.res.in 
      jrao@iict.res.in.
FAU - Madhu, Chakali
AU  - Madhu C
AD  - Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, 
      Hyderabad 500 007, India. manee03@gmail.com maneesha@iict.res.in 
      jrao@iict.res.in.
FAU - Reddy, Vanammoole Lakshmi
AU  - Reddy VL
AD  - Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, 
      Hyderabad 500 007, India. manee03@gmail.com maneesha@iict.res.in 
      jrao@iict.res.in.
FAU - Paramasivam, Mahalingavelar
AU  - Paramasivam M
AD  - Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, 
      Hyderabad 500 007, India. manee03@gmail.com maneesha@iict.res.in 
      jrao@iict.res.in.
FAU - Bangal, Prakriti Ranjan
AU  - Bangal PR
AUID- ORCID: 0000-0002-0355-2025
AD  - Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical 
      Technology, Hyderabad 500 007, India. prakriti@iict.res.in.
FAU - Rao, Vaidya Jayathirtha
AU  - Rao VJ
AD  - Crop Protection Chemicals Division, CSIR-Indian Institute of Chemical Technology, 
      Hyderabad 500 007, India. manee03@gmail.com maneesha@iict.res.in 
      jrao@iict.res.in.
LA  - eng
PT  - Journal Article
PL  - England
TA  - Phys Chem Chem Phys
JT  - Physical chemistry chemical physics : PCCP
JID - 100888160
EDAT- 2017/03/21 06:00
MHDA- 2017/03/21 06:01
CRDT- 2017/03/21 06:00
PHST- 2017/03/21 06:00 [pubmed]
PHST- 2017/03/21 06:01 [medline]
PHST- 2017/03/21 06:00 [entrez]
AID - 10.1039/c7cp00261k [doi]
PST - ppublish
SO  - Phys Chem Chem Phys. 2017 Mar 29;19(13):9118-9127. doi: 10.1039/c7cp00261k.