title: Computational study of the electronic structures, UV-Vis spectra and static second-order nonlinear optical susceptibilities of macrocyclic thiophene derivatives.
abstract: Using thiophene (which has a moderate resonance energy) as a spacer rather than benzene permits better π-electron delocalization and leads to a large nonlinear optical response. Thus, the nonlinear optical coefficients of a series of macrocyclic thiophene derivatives (C[3T_DA](n) with C(n) symmetry) were studied, and their electronic structures, UV-Vis spectra and static second-order nonlinear optical susceptibilities (β(0)) were computed. The calculated results showed that ΔE(H-L) increased and the UV-Vis spectrum redshifted as the number of C[3T_DA] units increased (one C[3T_DA] unit consists of trithiophene and diacetylene). The value of β(0) calculated by either the ZINDO-SOS or the FF method showed the same trend: the absolute value of β(0) increased as the number of units increased. The value of β(0) predicted by ZINDO-SOS was an order of magnitude larger than that predicted by the FF method. However, the results suggest that macrocyclic thiophene compounds potentially exhibit large static second-order nonlinear optical susceptibilities.
authors.affiliation: State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Huang
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Ren
authors.forename: Lu-Yi
authors.initials: LY
authors.lastname: Zou
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Jing-Fu
authors.initials: JF
authors.lastname: Guo
authors.forename: Ji-Kang
authors.initials: JK
authors.lastname: Feng
mesh_terms: D003198:Computer Simulation; D004583:Electrons; D047028:Macrocyclic Compounds / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D056951:Photoelectron Spectroscopy; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D047028:Macrocyclic Compounds; D013876:Thiophenes