Impact of exact exchange in the description of the electronic structure of organic charge-transfer molecular crystals

Handle URI:
http://hdl.handle.net/10754/555960
Title:
Impact of exact exchange in the description of the electronic structure of organic charge-transfer molecular crystals
Authors:
Fonari, Alexandr; Sutton, Christopher; Bredas, Jean-Luc ( 0000-0001-7278-4471 ) ; Coropceanu, Veaceslav
Abstract:
We evaluate the impact that the amount of nonlocal Hartree-Fock (%HF) exchange included in a hybrid density functional has on the microscopic parameters (transfer integrals, band gaps, bandwidths, and effective masses) describing charge transport in high-mobility organic crystals. We consider both crystals based on a single molecule, such as pentacene, and crystals based on mixed-stack charge-transfer systems, such as dibenzo-TTF–TCNQ. In the pentacene crystal, the band gap decreases and the effective masses increase linearly with an increase in the amount of %HF exchange. In contrast, in the charge-transfer crystals, while the band gap increases linearly, the effective masses vary only slightly with an increase in %HF exchange. We show that the superexchange nature of the electronic couplings in charge-transfer systems is responsible for this peculiar evolution of the effective masses. We compare the density functional theory results with results obtained within the G0W0 approximation as a way of benchmarking the optimal amount of %HF exchange needed in a given functional.
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Citation:
Impact of exact exchange in the description of the electronic structure of organic charge-transfer molecular crystals 2014, 90 (16) Physical Review B
Journal:
Physical Review B
Issue Date:
21-Oct-2014
DOI:
10.1103/PhysRevB.90.165205
Type:
Article
ISSN:
1098-0121; 1550-235X
Additional Links:
http://link.aps.org/doi/10.1103/PhysRevB.90.165205
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorFonari, Alexandren
dc.contributor.authorSutton, Christopheren
dc.contributor.authorBredas, Jean-Lucen
dc.contributor.authorCoropceanu, Veaceslaven
dc.date.accessioned2015-05-28T07:24:56Zen
dc.date.available2015-05-28T07:24:56Zen
dc.date.issued2014-10-21en
dc.identifier.citationImpact of exact exchange in the description of the electronic structure of organic charge-transfer molecular crystals 2014, 90 (16) Physical Review Ben
dc.identifier.issn1098-0121en
dc.identifier.issn1550-235Xen
dc.identifier.doi10.1103/PhysRevB.90.165205en
dc.identifier.urihttp://hdl.handle.net/10754/555960en
dc.description.abstractWe evaluate the impact that the amount of nonlocal Hartree-Fock (%HF) exchange included in a hybrid density functional has on the microscopic parameters (transfer integrals, band gaps, bandwidths, and effective masses) describing charge transport in high-mobility organic crystals. We consider both crystals based on a single molecule, such as pentacene, and crystals based on mixed-stack charge-transfer systems, such as dibenzo-TTF–TCNQ. In the pentacene crystal, the band gap decreases and the effective masses increase linearly with an increase in the amount of %HF exchange. In contrast, in the charge-transfer crystals, while the band gap increases linearly, the effective masses vary only slightly with an increase in %HF exchange. We show that the superexchange nature of the electronic couplings in charge-transfer systems is responsible for this peculiar evolution of the effective masses. We compare the density functional theory results with results obtained within the G0W0 approximation as a way of benchmarking the optimal amount of %HF exchange needed in a given functional.en
dc.relation.urlhttp://link.aps.org/doi/10.1103/PhysRevB.90.165205en
dc.rightsArchived with thanks to Physical Review Ben
dc.titleImpact of exact exchange in the description of the electronic structure of organic charge-transfer molecular crystalsen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalPhysical Review Ben
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionSchool of Chemistry and Biochemistry and Center for Organic Photonics and Electronics Georgia Institute of Technology Atlanta, Georgiaen
kaust.authorBredas, Jean-Lucen
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