Rutherfordium: Béda antara owahan

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==Official discovery==

Element 104 was reportedly [[discovery of the chemical elements|first detected]] in 1966 at the [[JINR|Joint Institute of Nuclear Research ]] at [[Dubna]] ([[U.S.S.R.]]). Researchers there bombarded ²⁴²[[plutonium|Pu]] with accelerated ²²[[neon|Ne]] [[ion]]s and separated the reaction products by gradient thermochromatography after conversion to chlorides by interaction with ZrCl₄. The team identified a [[spontaneous fission]] activity contained within a volatile chloride portraying eka-hafnium properties. Although a half-life was not accurately determined, later calculations indicated that the product was most likely ²⁵⁹Rf:<ref name=93TWG>[http://www.iupac.org/publications/pac/1993/pdf/6508x1757.pdf "DISCOVERY OF THE TRANSFERMIUM ELEMENTS"], '''IUPAC/IUPAP Technial Report''', ''Pure & Appl. Chem.'', Vol. 65, No. 8, pp. 1757-1814,1993. Retrieved on [[2008-03-04]]</ref>

 

:<math>\, ^{242}_{94}\mathrm{Pu} + \, ^{22}_{10}\mathrm{Ne} \to \, ^{264-x}_{104}\mathrm{Rf}\to \,^{264-x}_{104}\mathrm{RfCl}_{4}</math>

===Chemistry===

In an analogous manner to zirconium and hafnium, rutherfordium is projected to form a very stable, high melting point oxide, RfO₂. It should also react with halogens to form tetrahalides, RfX₄, which hydrolyse on contact with water to form oxyhalides RfOX₂. The tetrahalides should be volatile solids existing as monomeric tetrahedral molecules in the vapour phase.

 

==Experimental chemistry==

<ref>[http://www.springerlink.com/content/m87v320736564810/ "Experiments on the synthesis of neutron-deficient isotopes of kurchatovium in reactions with accelerated ⁵⁰Ti ions"], '''Oganesyan et al'''., ''Nucl. Phys. A.'', 1975, 36, 6. Retrieved on [[2008-02-29]]</ref>

The reaction was further studied in 1985 by the GSI team who measured the decay properties of the isotopes ²⁵⁷Rf and ²⁵⁶Rf. The team were able to determine some initial spectroscopic properties of ²⁵⁷Rf and found that the alpha decay pattern was very complicated.

 

After an upgrade of their facilities, they repeated the reaction in 1994 with much higher sensitivity and detected some 1100 atoms of ²⁵⁷Rf and 1900 atoms of ²⁵⁶Rf along with ²⁵⁵Rf in the measurement of the 1n,2n and 3n excitation functions. The large amount of decay data for ²⁵⁷Rf allowed the detection of an isomeric level and the construction of a partial decay level structure which confirmed the very complicated alpha decay pattern. They also found evidence for an isomeric level in ²⁵⁵Rf.

===²⁰⁷Pb(⁵⁰Ti,xn)^257-xRf (x=2)===

This reaction was first studied in 1974 by the team at Dubna. They measured a spontaneous fission activity assigned to ²⁵⁵Rf. The reaction was further studied in 1985 by the GSI team who measured the decay properties of the isotope ²⁵⁵Rf. A further spectroscopic study was reported in 2000 which led to a first decay level scheme for the isotope.<ref>[http://www.edpsciences.org/articles/epja/abs/2001/09/epja1103/epja1103.html "Decay properties of neutron-deficient isotopes ^256,257Db, ²⁵⁵Rf, ^252,253Lr"], '''Hessberger et al.''', ''Eur. Phys. J.'', A 12, 57-67 (2001). Retrieved on [[2008-02-29]]</ref> The isomeric level proposed in 1994 was not found. In 2006, the spectroscopy was continued and the decay scheme was confirmed and improved.

 

===²⁰⁶Pb(⁵⁰Ti,xn)^256-xRf (x=1,2)===

The reaction was further studied in 2000 by Yuri Lazarev and the team at Dubna. They were able to observe 69 alpha decays from ²⁶¹Rf and [[spontaneous fission]] of ²⁶²Rf.

<ref>[http://prola.aps.org/abstract/PRC/v62/i6/e064307 "Decay properties of ²⁵⁷No, ²⁶¹Rf, and ²⁶²Rf"], '''Lazarev et al.''', ''Phys. Rev. C 62'', 064307 (2000). Retrieved on [[2008-03-04]]</ref>

 

===²⁴²Pu(²²Ne,xn)^264-xRf (x=3,4?,5?)===

 

===²⁴⁸Cm(¹⁶O,xn)^264-xRf (x=4)===

 

===²⁴⁶Cm(¹⁸O,xn)^264-xRf===

 

===²⁴⁹Bk(¹⁵N,xn)^264-xRf (x=4)===

This reaction was studied in 1977 by the team in Dubna. They were able to confirm the detection of a 76 ms SF activity. The assignment to rutherfordium isotopes was later retracted.

 

===²⁴⁹Cf(¹³C,xn)^262-xRf (x=4)===

 

===²⁴⁹Cf(¹²C,xn)^261-xRf (x=3,4)===

===²⁶⁸Rf===

In the synthesis of [[ununpentium]], the isotope ²⁸⁸115 has been observed to decay to ²⁶⁸Db which undergoes [[spontaneous fission]] with a half life of 29 hours. Given that the [[electron capture]] of ²⁶⁸Db cannot be detected, these SF events may in fact be due to the SF of ²⁶⁸Rf, in which case the half-life of this isotope cannot be extracted.

 

===²⁶⁶Rf===

==Retracted isotopes==

===²⁶⁵Rf===

 

===^255mRf===

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