Potassium dihydrogen phosphate
|Product name||Potassium dihydrogen phosphate|
Main content (KH2PO4)
Fertilizer-grade MKP powder contains the equivalent of 52% P2O5 and 34% K2O, and is labeled NPK 0-52-34.
MKP powder is often used as a nutrient source in the greenhouse trade and in hydroponics.
As a crystal, MKP is noted for its non-linear optical properties. Used in optical modulators and for non-linear optics such as second-harmonic generation
Also to be noted is KDP, potassium dideuterium phosphate, with slightly different properties. Highly deuterated KDP is used in nonlinear frequency conversion of laser light instead of protonated (regular) KDP due to the fact that the replacement of protons with deuterons in the crystal shifts the third overtone of the strong OH molecular stretch to longer wavelengths, moving it mostly out of the range of the fundamental line at ~1064 nm of neodymium-based lasers. Regular KDP has absorbances at this wavelength of approximately 4.7–6.3% per cm of thickness while highly deuterated KDP has absorbances of typically less than 0.8% per cm.