Nonlinear optical and electrooptical effects in 2-methyl-4-nitro-N-methylaniline (MNMA) crystals

Single crystals of 2-methyl-4-nitro-N-methylaniline (MNMA) have been grown from the melt. The crystal structure was determined (orthorhombic, Pna2/sub I/ (2 mm), Z=4, a=17.788(6) AA, b=11.893(4) AA, c=3.907(2) AA). The refractive indexes n/sub a/ and n/sub c/ were measured between 500 and 700 nm (n/sub a/(633 nm)=2.148(10), n/sub c/(633 nm)=1.520(3)). The nonlinear optical susceptibilities coefficients r/sub 31/=8 pm/V and r/sub 33/=7.5 pm/V were determined. Most optical properties can be explained in terms of molecular orientation and polarizability.<
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