Second harmonic generation in push-pull ethylenes: Influence of chirality and hydrogen bonding

Article abstract of DOI:10.1016/0022-2860(95)09180-7

The effect of chiral substituents and hydrogen bonding functional groups on the microscopic and macroscopic second-order non-linearities in some donor-acceptor substituted ethylenes has been investigated. It appears that extensive intramolecular and intermolecular hydrogen bonding helps to improve both the microscopic hyperpolarizability (β) as well as the powder second harmonic generation (SHG) efficiency in these compounds. The substitution of the chiral α-methylbenzylamine donor guarantees a non-centrosymmetric structure. Cocrystallization with triphenylphosphine oxide (TPPO) does not appear to yield better SHG efficiency in the α-methylbenzylamine substituted ethylene compound which has an extended hydrogen bonding network.