Optical absorption measurements made at 10 K on Cs2NaErCl6 in the rang
e 6000 to 26 000 cm(-1) are analysed. Absolute line intensities of the
transitions are used to predict dipole strengths and intrinsic intens
ity parameters ((A) over bar(t) lambda) using 60 of the observed oscil
lator strengths with data from three different modes of oscillation. R
esults are consistent with intensity calculations in other systems.