Modeling the electric field third-order nonlinear responses of an infinite aggregate of hexatriene chains using the electrostatic interaction model

Abstract

A classical electrostatic polarization scheme using the additive distribution procedure has been applied to determine the static longitudinal polarizability and second hyperpolarizability of a all-trans hexatriene molecule in an infinite stretched fiber. The parameters have been derived from ab initio coupled-perturbed Hartree-Fock calculations and the electrostatic scheme has been validated via comparison with ab initio results on small clusters. Upon packing, the polarizability of all-trans hexatriene increases by 7% whereas the second hyperpolarizability increases by as much as 61%. These increases result from the balance between the enhancement of the (hyper)polarizability due to collinear packing and the reduction associated with lateral packing.

On the weak intermolecular interactions and their influence on the optical properties of unsaturated hydrocarbons. Part 1: Two-body interactions

“…A similar tendency was observed in the linear complexes of acetylene molecules [24] as well as in the infinite stretched fibres of all-trans hexatriene molecules [25]. Although Champagne et al [25] suggested that upon packing, the polarizability and the second hyperpolarizability of hexatriene molecules increase significantly, their studies reveal that this is in fact due to the balance between the enhancement resulting from collinear packing and the reduction associated with lateral packing, similarly to the other abovementioned cases. In contrast, the linear and nonlinear optical response of polyene chains in solution is substantially enhanced, even for solvents with relatively low polarity [26,27].…”

“…The results of ab initio calculations indicate that in the case of small all-trans polyene chains, mutual interactions lead to considerable reduction in values of molecular polarizability and second-order hyperpolarizability [12,14,[20][21][22][23]. A similar tendency was observed in the linear complexes of acetylene molecules [24] as well as in the infinite stretched fibres of all-trans hexatriene molecules [25]. Although Champagne et al [25] suggested that upon packing, the polarizability and the second hyperpolarizability of hexatriene molecules increase significantly, their studies reveal that this is in fact due to the balance between the enhancement resulting from collinear packing and the reduction associated with lateral packing, similarly to the other abovementioned cases.…”

Charge-Transfer Interactions in Organic Functional Materials

“…The excited-state wavefunctions of the monomer were obtained by the single configuration-interaction (SCI) scheme [60] with all occupied and unoccupied π-levels included within the semiempirical Pariser-Parr-Pople (PPP) Hamiltonian [56,57,72] which has been used extensively in the studies of conjugated molecules, and has given reliable results for spectroscopic and other linear or nonlinear optical properties when compared with experimental results and computationally highly extensive ab-initio calculations [73,74,75]. The reason why we chose this simple p-orbital based PPP model is that it is believed that the electronic and optical properties of conjugated molecules lie in the p orbitals of the backbone atoms, which overlap to form delocalized p molecule orbitals [76].…”

Electrostatic modeling of the linear optical susceptibilities of 2-methyl-4-nitroaniline, m-nitroaniline, 3-methyl-4-nitropyridine N-oxide and 2-carboxylic acid-4-nitropyridine-1-oxide crystals

“…The oriented gas model, generally attributed to Oudar and co-workers [5,6], assumes that (hyper)polarizabilities are additive, and hence bulk susceptibilities can be obtained from a straightforward tensor sum over the microscopic (molecular) properties for the unit cell. Interaction schemes can be viewed as an evolution of the oriented gas approximation where field tensor effects are evaluated using the molecular properties [7][8][9][10][11][12]. Cluster and aggregate approaches also provide complementary information, often based on systems of moderate size [13][14][15][16][17][18][19] whereas crystal orbital methods (also called band structure methods) deal with periodic infinite systems [20][21][22].…”