XmlmmCIF equivalent: diffrn_radiation_wavelength Data items in the DIFFRN_RADIATION_WAVELENGTH category describe the wavelength of radiation used in measuring diffraction intensities. Items may be looped to identify and assign weights to distinct components of a polychromatic beam. XmlmmCIF equivalent: diffrn_radiation_wavelength/wavelength The radiation wavelength in angstroms. XmlmmCIF equivalent: diffrn_radiation_wavelength/wt The relative weight of a wavelength identified by the code _diffrn_radiation_wavelength.id in the list of wavelengths. XmlmmCIF equivalent: diffrn_radiation_wavelength/id The code identifying each value of _diffrn_radiation_wavelength. Items in the DIFFRN_RADIATION_WAVELENGTH category are looped when multiple wavelengths are used. This code is used to link with the DIFFRN_REFLN category. The _diffrn_refln.wavelength_id codes must match one of the codes defined in this category.