We have measured both phase difference decrease delta between ordinary and extraordinary rays passing through liquid crystal cell and dielectric constants epsilon of 4-trans-n-hexyl-cyclohekxylisothiocyanatobenzene (6CHBT). The results of the studies for different alignment and thicknesses under various electric measuring and magnetic fields are presented. The exposed experimental technique and data processing allows K-11 and K-33 determination. Determination Theta(Z) is derived from continuum theory so it is not purely experimental determination but semiempirical method.