TY - JOUR
T1 - Origins of Singlet Fission in Solid Pentacene from an ab initio Green's Function Approach
AU - Refaely-Abramson, Sivan
AU - da Jornada, Felipe H.
AU - Louie, Steven G.
AU - Neaton, Jeffrey B.
N1 - This work was supported by the Center for Computational Study of Excited-State Phenomena in Energy Materials (C2SEPEM) at the Lawrence Berkeley National Laboratory, which is funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division under Contract No. DE-AC02-05CH11231, as part of the Computational Materials Sciences Program. Work performed at the Molecular Foundry was also supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under the same contract number. S. R. A. acknowledges support from Rothschild and Fulbright fellowships. We thank Eran Rabani and Naomi S. Ginsberg for valuable discussions, and Diana Y. Qiu for helpful code development. This research used resources of the National Energy Research Scientific Computing Center (NERSC). S. R. A. and F. H. J. contributed equally to this work.
PY - 2017/12/29
Y1 - 2017/12/29
N2 - We develop a new first-principles approach to predict and understand rates of singlet fission with an ab initio Green's-function formalism based on many-body perturbation theory. Starting with singlet and triplet excitons computed from a GW plus Bethe-Salpeter equation approach, we calculate the exciton-biexciton coupling to lowest order in the Coulomb interaction, assuming a final state consisting of two noninteracting spin-correlated triplets with finite center-of-mass momentum. For crystalline pentacene, symmetries dictate that the only purely Coulombic fission decay process from a bright singlet state requires a final state consisting of two inequivalent nearly degenerate triplets of nonzero, equal and opposite, center-of-mass momenta. For such a process, we predict a singlet lifetime of 30-70 fs, in very good agreement with experimental data, indicating that this process can dominate singlet fission in crystalline pentacene. Our approach is general and provides a framework for predicting and understanding multiexciton interactions in solids.
AB - We develop a new first-principles approach to predict and understand rates of singlet fission with an ab initio Green's-function formalism based on many-body perturbation theory. Starting with singlet and triplet excitons computed from a GW plus Bethe-Salpeter equation approach, we calculate the exciton-biexciton coupling to lowest order in the Coulomb interaction, assuming a final state consisting of two noninteracting spin-correlated triplets with finite center-of-mass momentum. For crystalline pentacene, symmetries dictate that the only purely Coulombic fission decay process from a bright singlet state requires a final state consisting of two inequivalent nearly degenerate triplets of nonzero, equal and opposite, center-of-mass momenta. For such a process, we predict a singlet lifetime of 30-70 fs, in very good agreement with experimental data, indicating that this process can dominate singlet fission in crystalline pentacene. Our approach is general and provides a framework for predicting and understanding multiexciton interactions in solids.
UR - http://www.scopus.com/inward/record.url?scp=85039760591&partnerID=8YFLogxK
U2 - 10.1103/PhysRevLett.119.267401
DO - 10.1103/PhysRevLett.119.267401
M3 - مقالة
SN - 0031-9007
VL - 119
JO - Physical review letters
JF - Physical review letters
IS - 26
M1 - 267401
ER -