Abstract by Gabriel Valdivi
Chemistry and Biochemistry
Optimal packing for molecular terahertz generation crystals: just one carbon away
Organic nonlinear optical materials are used for a wide range of applications, including terahertz (THz) light generation. Several strategies have been designed to disrupt anti-parallel arrangements due to dipole-dipole interactions that lead to centrosymmetric structures because non-centrosymmetric packing is essential to obtain a second-order material response. We will show that a cation modification of substituting a methyl by an ethyl group in the ubiquitous organic salt quaternary nitrogen moiety can change a crystal from centro to non-centrosymmetric. This molecular packing behavior is attributed to site-isolation effects promoted by the ethyl group as shown with Hirshfeld interaction surfaces. This simple engineering strategy impacts the way molecular cations for NLO applications may be designed.