Californium most dangerous if taken into the body. In addition, californium-249 and californium-251 can cause tissue damage externally, through gamma ray emission. Ionizing radiation emitted by californium on bone and in the liver can cause cancer. Californium Californium is a radioactive chemical element with symbol Cf and atomic number 98. The element was first synthesized in 1950 at the Lawrence Berkeley National Laboratory (then the University of California Radiation Laboratory), by bombarding curium with alpha particles (helium-4 ions). It is an actinide element, the sixth transuranium element to be synthesized, and has the second-highest atomic mass of all the elements that
Californium compounds hexagonal structure. Californium(III) iodide (CfI) is a lemon-yellow solid that has a rhombohedral structure and sublimes at ~800 °C. Californium(III) oxyfluoride (CfOF) is prepared by hydrolysis of californium(III) fluoride (CfF) at high temperature. Californium(III) oxychloride (CfOCl) is prepared by hydrolysis of the hydrate of californium(III) chloride at 280–320 °C. Heating the sulfate in air at about 1200 °C and then reducing with hydrogen at 500 °C produces the sesquioxide (CfO). The hydroxide Cf(OH) and the trifluoride CfF are slightly soluble. Californium(III) oxychloride (CfOCl) was the first californium compound to be discovered. Californium(III) polyborate is unusual in that californium is covalently