The compressibility of hexagonal graphite-like boron nitride has been
measured at room temperature up to 12 GPa, using a diamond anvil cell
and X-ray scattering with synchrotron radiation. From the obtained pre
ssure-volume relation for hBN the isothermal bulk modulus of 36.7+/-0.
5 GPa and its first pressure derivative of 5.6+/-0.2 have been calcula
ted.