Isotopes of californium Isotopes of californium Californium (Cf) is an artificial element, and thus a standard atomic weight cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was Cf in 1950. There are 20 known radioisotopes ranging from Cf to Cf and one nuclear isomer, Cf. The longest-lived isotope is Cf with a half-life of 900 years. Californium-252 (Cf-252) undergoes spontaneous fission and is used in small sized neutron sources. Fission neutrons have an energy range of 0 to 13 MeV with a mean value of 2.3 MeV and a most probable value of
Californium(III) polyborate elements emit α particles, gamma rays and neutrons. Californium(III) polyborate Californium polyborate is a covalent compound with formula Cf[BO(OH)]. In this compound the californium is in a +3 oxidation state. Californium polyborate is unusual in that californium is covalently bound to the borate. Californium was expected to resemble lanthanide elements in being highly ionic. The polyborate anion is polarisable and flexible. The 5f, 6d, 7s, and 7p orbitals of californium are all involved on the bonding. Most valence electrons are in the 5f orbital, and a significant fraction () in the 6d orbital, and smaller fractions of one electron are