Californium Elemental Symbol

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Californium Californium Californio Califórnio Californium Californium

Californium Bohr ModelCalifornium is a Block F, Group 3, Period 7 element. The number of electrons in each of californium's shells is 2, 8, 18, 32, 28, 8, 2 and its electron configuration is [Rn] 5f10 7s2. The californium atom has a radius of In its elemental form, californium's CAS number is 7440-71-3. Californium is radioactive and therefore harmful. Californium's f electrons are further removed from the valence electrons than those of the lighter actinides so it resembles the behavior of the lanthanide elements by exhibiting divalent, trivalent, and tetravalent oxidation states in solid-state compounds. Because it's a very efficient source of neutrons, many new uses are expected for it. Californium was discovered by Stanley G. Thompson, Kenneth Street Jr. and Albert Ghiorso at the Lawrence Berkeley National Laboratory in 1950. The element was named in honor of the state of California and for the University of California, Berkeley, USA. It was the sixth transuranium element of the actinide series to be discovered.

Californium information, including technical data, safety data and its high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on earth, conductivity and thermal properties are included.

  • Properties
  • Research
  • Isotopes
  • Other Elements

Californium Properties

Symbol: Cf Melting Point: 900 oC, 1652 oF, 1173.15 K
Atomic Number: 98 Boiling Point: 1470 °C, 2678 °F, 1743 K (est.)
Atomic Weight: 251 Density: 15.1 g·cm−3
Element Category: Actinide Liquid Density @ Melting Point: N/A
Group, Period, Block: n/a, 7, f Specific Heat: N/A
    Heat of Vaporization N/A
Electrons: 98 Thermal Conductivity: N/A
Protons: 98 Thermal Expansion: N/A
Neutrons: 153 Electrical Resistivity: N/A
Electron Configuration: [Rn] 5f107s2 Electronegativity: 1.3 (Pauling scale)
Atomic Radius: pm (estimated) Tensile Strength: N/A
Covalent Radius: pm (estimated) Molar Heat Capacity: N/A
Van der Waals radius: N/A Young's Modulus: N/A
Oxidation States: 2, 3, 4 Shear Modulus: N/A
Phase: Solid Bulk Modulus: N/A
Crystal Structure: hexagonal Poisson Ratio: N/A
Magnetic Ordering: N/A Mohs Hardness: 3-4
1st Ionization Energy: 608 kJ·mol−1 (estimated) Vickers Hardness: N/A
2nd Ionization Energy: N/A Brinell Hardness: N/A
3rd Ionization Energy: N/A Speed of Sound: N/A
CAS Number: 7440-71-3 Abundance in typical human body, by weight: N/A
ChemSpider ID: 22433 Abundance in typical human body, by atom: N/A
PubChem CID: 23997 Abundance in universe, by weight: N/A
MDL Number: N/A Abundance in universe, by atom: N/A
EC Number: N/A Discovered By: Lawrence Berkeley Nat'l Laboratory
Beilstein Number: N/A Discovery Date: 1950
SMILES Identifier: [Cf]  
InChI Identifier: InChI=1S/Cf Other Names: Californio

Recent Research & Development for Californium

  • Early-stage esophageal squamous cell carcinoma treated with californium-252 neutron brachytherapy: clinical report on 16 cases. Liu H, Wang Q, Jia X, Liu B, Wang CK. Tumori. 2013 Mar-Apr;99(2):172-5. doi: 10.1700/1283.14188.
  • Optical transitions in highly charged californium ions with high sensitivity to variation of the fine-structure constant. Berengut JC, Dzuba VA, Flambaum VV, Ong A. Phys Rev Lett. 2012 Aug 17;109(7):070802. Epub 2012 Aug 16.
  • Development of electron beam ion source charge breeder for rare isotopes at Californium Rare Isotope Breeder Upgrade. Kondrashev S, Dickerson C, Levand A, Ostroumov PN, Pardo RC, Savard G, Vondrasek R, Alessi J, Beebe E, Pikin A, Kuznetsov GI, Batazova MA. Rev Sci Instrum. 2012 Feb;83(2):02A902. doi: 10.1063/1.3660823.
  • Design of the injection beamline for the Californium Rare Isotope Breeder Upgrade electron beam ion source charge breeder. Dickerson CA, Mustapha B, Kondrashev S, Ostroumov PN, Savard G, Levand A, Pikin A. Rev Sci Instrum. 2012 Feb;83(2):02A502. doi: 10.1063/1.3662958.
  • Low-dose-rate californium-252 neutron intracavitary afterloading radiotherapy combined with conformal radiotherapy for treatment of cervical cancer. Zhang M, Xu HD, Pan SD, Lin S, Yue JH, Liu JR. Int J Radiat Oncol Biol Phys. 2012 Jul 1;83(3):966-71. doi: 10.1016/j.ijrobp.2011.08.031. Epub 2011 Dec 3.
  • Californium-252 brachytherapy combined with external-beam radiotherapy for cervical cancer: long-term treatment results. Lei X, Qian CY, Qing Y, Zhao KW, Yang ZZ, Dai N, Zhong ZY, Tang C, Li Z, Gu XQ, Zhou Q, Feng Y, Xiong YL, Shan JL, Wang D. Int J Radiat Oncol Biol Phys. 2011 Dec 1;81(5):1264-70. doi: 10.1016/j.ijrobp.2010.08.039. Epub 2011 Mar 23.
  • Solving the hydration structure of the heaviest actinide aqua ion known: the californium(III) case. Galbis E, Hernández-Cobos J, den Auwer C, Le Naour C, Guillaumont D, Simoni E, Pappalardo RR, Sánchez Marcos E. Angew Chem Int Ed Engl. 2010 May 17;49(22):3811-5. doi: 10.1002/anie.200906129. No abstract available.
  • Results with the electron cyclotron resonance charge breeder for the 252Cf fission source project (Californium Rare Ion Breeder Upgrade) at Argonne Tandem Linac Accelerator System. Vondrasek R, Kondrashev S, Pardo R, Scott R, Zinkann GP. Rev Sci Instrum. 2010 Feb;81(2):02A907. doi: 10.1063/1.3272803.
  • Clinical report on external irradiation combined with californium-252 neutron intraluminal brachytherapy for cervical carcinoma treatment. Zhao H, Wang K, Sun J, Geng X, Zhang W. Tumori. 2007 Nov-Dec;93(6):636-40.
  • [Follow-up study of clinical effects of californium-252 neutron intracavitary radiotherapy and external beam radiotherapy in endometrial cancer]. Lei X, Shan JL, Tang C, Zhao KW. Zhonghua Fu Chan Ke Za Zhi. 2007 Nov;42(11):733-6. Chinese.
  • First structural determination of a trivalent californium compound with oxygen coordination. Sykora RE, Assefa Z, Haire RG, Albrecht-Schmitt TE. Inorg Chem. 2006 Jan 23;45(2):475-7.
  • [The preliminary report of cervical cancer treated with californium-252 neutron after loading intracavitary radiotherapy]. Luo G, Zheng C, Shan J. Zhonghua Fu Chan Ke Za Zhi. 2001 Dec;36(12):742-4. Chinese.
  • Hypoxic versus normoxic external-beam irradiation of cervical carcinoma combined with californium-252 neutron brachytherapy. Comparative treatment results of a 5-year randomized study. Tacev T, Vacek A, Ptácková B, Strnad V. Strahlenther Onkol. 2005 May;181(5):273-84.
  • Dietary nucleosides and nucleotides do not affect tumor incidence but reduce amyloidosis incidence in B6C3F1 mice irradiated with californium-252. Yokoyama H, Fujiwara H, Watanabe H. Nutrition. 2004 Apr;20(4):383-9.
  • Californium-252 (252Cf) versus conventional gamma radiation in the brachytherapy of advanced cervical carcinoma long-term treatment results of a randomized study. Tacev T, Ptácková B, Strnad V. Strahlenther Onkol. 2003 Jun;179(6):377-84.
  • Remote afterloading for neutron brachytherapy using californium-252. Tacev T, Grigorov G, Papírek T, Kolarík V. Strahlenther Onkol. 2003 Feb;179(2):113-7.
  • Production, distribution and applications of californium-252 neutron sources. Martin RC, Knauer JB, Balo PA. Appl Radiat Isot. 2000 Oct-Nov;53(4-5):785-92. Review.
  • Early changes in flow cytometric DNA profiles induced by californium-252 neutron brachytherapy in squamocellular carcinomas of the uterine cervix. Tacev T, Zaloudík J, Janáková L, Vagunda V. Neoplasma. 1998;45(2):96-101.
  • [An improved method of preparing protein and peptide probes in mass spectrometry with ionization of division fragments by californium-252 (TOF-PDMS)]. Chivanov VD, Zubarev RA, Aksenov SA, Bordunova OG, Eremenko VI, Kabanets VM, Tatarinova VI, Mishnev AK, Kuraev VV, Knysh AN, Eremenko IA. Bioorg Khim. 1996 Aug;22(8):585-8. Russian.
  • [Use of time-of-flight mass spectrometry with ionization division fragments of californium-252 for studying the mechanisms of action of drugs on DNA and its components]. Sukhodub LF, Grebenik LI, Chivanov VD. Biofizika. 1994 Mar-Apr;39(2):289-93. Russian.

Californium Isotopes

Trace quantities of californium are found in nature from neutron capture by uranium atoms; however, the element is mainly produced artificially and has no stable isotopes.