Dispersion of the vectorial part of DCNP molecular second order hyperpolarizability beta(CT)(-2 omega;omega,omega) was calculated from solvatochromic method supplemented with a separately measured ground state dipole moment of DCNP and from quantum-mechanical calculations basing on two-level model. Photoconductivity and pyroelectric properties of DCNP combined with large electrooptic coefficient observed in this material may be useful in formation of transient gratings.