Second Harmonic Generation, Electrooptical Pockels Effect, and Static First-Order Hyperpolarizabilities of 2,2′-Bithiophene Conformers : An HF, MP2, and DFT Theoretical Investigation
Author
Source
Advances in Physical Chemistry
Issue
Vol. 2013, Issue 2013 (31 Dec. 2013), pp.1-8, 8 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2013-12-16
Country of Publication
Egypt
No. of Pages
8
Main Subjects
Abstract EN
The static and dynamic electronic (hyper)polarizabilities of the equilibrium conformations of 2,2′-bithiophene (anti-gauche and syn-gauche) were computed in the gas phase.
The calculations were carried out using Hartree-Fock (HF), Møller-Plesset second-order perturbation theory (MP2), and density functional theory methods.
The properties were evaluated for the second harmonic generation (SHG), and electrooptical Pockels effect (EOPE) nonlinear optical processes at the typical λ=1064 nm of the Nd:YAG laser.
The anti-gauche form characterized by the S–C2–C2′–S dihedral angle of 137° (MP2/6-311G**) is the global minimum on the potential energy surface, whereas the syn-gauche rotamer (S–C2–C2′–S = 48°, MP2/6-311G**) lies ca.
0.5 kcal/mol above the anti-gauche form.
The structural properties of the gauche structures are rather similar to each other.
The MP2 electron correlation effects are dramatic for the first-order hyperpolarizabilities of the 2,2′-bithiophenes, decreasing the HF values by ca.
a factor of three.
When passing from the anti-gauche to the syn-gauche conformer, the static and frequency-dependent first-order hyperpolarizabilities increase by ca.
a factor of two.
Differently, the electronic polarizabilities and second-order hyperpolarizabilities of these rotamers are rather close to each other.
The syn-gauche structure could be discriminated from the anti-gauche one through its much more intense SHG and EOPE signals.
American Psychological Association (APA)
Alparone, Andrea. 2013. Second Harmonic Generation, Electrooptical Pockels Effect, and Static First-Order Hyperpolarizabilities of 2,2′-Bithiophene Conformers : An HF, MP2, and DFT Theoretical Investigation. Advances in Physical Chemistry،Vol. 2013, no. 2013, pp.1-8.
https://search.emarefa.net/detail/BIM-468698
Modern Language Association (MLA)
Alparone, Andrea. Second Harmonic Generation, Electrooptical Pockels Effect, and Static First-Order Hyperpolarizabilities of 2,2′-Bithiophene Conformers : An HF, MP2, and DFT Theoretical Investigation. Advances in Physical Chemistry No. 2013 (2013), pp.1-8.
https://search.emarefa.net/detail/BIM-468698
American Medical Association (AMA)
Alparone, Andrea. Second Harmonic Generation, Electrooptical Pockels Effect, and Static First-Order Hyperpolarizabilities of 2,2′-Bithiophene Conformers : An HF, MP2, and DFT Theoretical Investigation. Advances in Physical Chemistry. 2013. Vol. 2013, no. 2013, pp.1-8.
https://search.emarefa.net/detail/BIM-468698
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-468698