Environment polarity characteristics of biomolecules as an important factor can enhance their optical behaviors. Hence, knowledge of environment polarity effects can give valuable information about the function of molecules in different phenomena. In this work, linear, first, and second-order hyperpolarizability of (E)-2-benzylidene-2,3-dihydro-5,6-dimethoxyinden-1-one as pharmacologically important compounds were studied in different environments. The analysis was done by using environment multi-parameter polarity parameters. According to the results, environment polarity has different effects on the linear and nonlinear optical properties of samples. A quantitative study indicated that general solvent effects play important roles in molecular linear behaviors. Furthermore, environments with strong hydrogen bond acceptor ability increase molecular nonlinearity. On the other hand, environment polarity indicated the same effects on the molecular first and second-order nonlinearity. In this case, the studies on the molecular first-order nonlinearity in different solvents can give valuable information about environment effects on the molecular higher-order nonlinearity.
