Phase-matchable optical nonlinearity in strontium formate and strontium formate dihydrate

Orthorhombic Sr(CHO
2
)
2
and Sr(CHO
2
)
2
ċ2H
2
O crystals allow phase-matched SHG and optical mixing in the near IR to UV region with nonlinear coefficients
d_{14} = 1.9
and 1.2 ċ 10
^-9
ESU, respectively and low sensitivity with respect to aperture walkoff and beam divergence.