In certain non-ferroelectric molecular crystals a static external electrical field applied during the growth in the high vacuum may induce effects of permanent poling or depoling through interaction with dipolar molecules getting attached to crystal faces. In centrosymmetric crystal structures a field may effect a substantial deviation from a 50%:50% fractional site occupation with respect to the molecular dipole orientation. For channel-type inclusion compounds the electric field may affect growth sectors as such as to annihilate polarity in one sector and to enhance polarity in symmetry related sectors. Numerical simulations are given to show the change in the spatial distribution of polarity, including its temperature dependence. (C) 2003 Elsevier B.V. All rights reserved.