YCa4O(BO3)(3) has been found to be 90 degrees phase-matchable for type-1 se
cond-harmonic generation at 0.4168 mum along the z-axis st 20 degreesC. The
improved Sellmeier equations of YCa4O(BO3)(3) that correctly reproduce our
new experimental data for second-harmonic and sum-frequency generation in
the 0.3547-1.9079 mum range are reported. In addition, the 90 degrees phase
-matching properties of GdxY1-xCa4O(BO3)(3) as a function of the Gd molal c
oncentration X are presented together with the empirical index formula.