Potassium dideuterium phosphate

Potassium dideuterium phosphate

Two unit cells of DKDP viewed close to the b axis
Names
IUPAC names
Potassium dideuterium phosphate
Identifiers
3D model (JSmol)
ChemSpider
EC Number
  • 237-357-9
  • InChI=1S/K.H3O4P/c;1-5(2,3)4/h;(H3,1,2,3,4)/q+1;/p-1/i/hD2
    Key: GNSKLFRGEWLPPA-ZSJDYOACSA-M
  • [2H]OP(=O)([O-])O[2H].[K+]
Properties
KD
2PO
4 or K2H2PO4
Molar mass 138.10 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Deuterated potassium dihydrogen phosphate (KD2PO4 or K2H2PO4) or DKDP single crystals are widely used in non-linear optics as the second, third and fourth harmonic generators for Nd:YAG and Nd:YLF lasers. They are also found in electro-optical applications as Q-switches for Nd:YAG, Nd:YLF, alexandrite and Ti-sapphire lasers, as well as for Pockels cells.[1]

DKDP is monopotassium phosphate (KDP, or KH2PO4), but using deuterium. Replacement of hydrogen by deuterium in DKDP lowers the frequency of O–H vibrations and their overtones (high-order harmonics). Absorption of light by those overtones is detrimental for the infrared lasers, which DKDP and KDP crystals are used for. Consequently, despite higher cost, DKDP is more popular than KDP.

DKDP crystals are grown by a water-solution method at usual level of deuteration >98%.

  1. ^ Encyclopedia of Laser Physics and Technology.