Synthesis, structure, and intense second harmonic generation of Λ-shaped s-triazine derivative

A second-order non-linear optical organic crystal, which is made up of Λ-shaped π-conjugated molecule named as 2-methyl-4,6-di(p-N,N-dimethylaminostyryl)-s-triazine (abbreviated to DASTA) with its two branches attaching to a s-triazine ring, has been synthesized. This crystal has been determined to be in non-centrosymmetric polar P21 space group. It exhibits a powder SHG intensity of 46.2 times that of urea under 1064 nm fundamental pecosecond laser pulses. The one-branched analogue, 2,4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine, has also been synthesized. However, it crystallizes into centrosymmetric P1¯ space group and is SHG inactive.