Rutherfordium element chemistry

Only for element 104 could the 6 d shell start to be filled. Chemistry is known for this element (Rutherfordium or Kurchatovium), although only few atoms have been synthesized. 

The synthesis of the transactinides is noteworthy from a chemical and a nuclear viewpoint. From the chemical point of view, rutherfordium (Z = 104) is important as an example of the first transactinide element. From Figure 15.1, we would expect rutherfordium to behave as a Group 4 (IVB) element, such as hafnium or zirconium, but not like the heavy actinides. Its solution chemistry, as deduced from chromatography experiments, is different from that of the actinides and resembles that of zirconium and hafnium. More recently, detailed gas chromatography has shown important deviations from expected periodic table trends and relativistic quantum chemical calculations. 

Many chemists go to school for years and earn the top college degree before they make important discoveries in the lab, but James Andrew Harris took a different path. Harris graduated from college with a basic degree in chemistry, but then served in the Army and worked in a company lab before joining the team that discovered the transuranium elements rutherfordium and dubnium. 

Tiirler, A. Gas Phase Chemistry of the Transactinide Elements Rutherfordium, Dubnium, and Seaborgium , in Habilitation Thesis, Bern University (1999). 

For element 104 the names Kurchatovium (Ku) and Rutherfordium (Rf) were proposed by the groups at Dubna and Berkeley, respectively, thereby emphasizing their claim to the discoveries. The International Union on Pure and Applied Chemistry (lUPAC) has now decided on the following names element 104 Rutherfordium (Rf), element 105 Dubnium (Db), element 106 Seaborgium (Sg), element 107 Bohrium (Bh), element 108 Hassium (Hs), and element 109 Meitnerium (Mt). In the Periodic Table and nuclide charts we have thus used io4Rf. 106 8 107 > 108 So far no names have been... 

There has been some controversy about the naming of the higher synthetic elements because of disputes about their discovery. A long-standing problem concerned element-104 (rutherfordium) which was formerly also known by its Russian name of kurchatovium. More recent confusion has been caused by differences between names suggested by the International Union of Pure and Applied Chemistry (lUPAC) and the names suggested by the American Chemical Union (ACU). 

When a scientist discovered a new element in the early days of chemistiy, he or she had the honor of naming it. Now researchers must submit their choices for a name to an international committee called the International Union of Pure and Applied Chemistry before they can be placed on the periodic table. In 1997, the lUPAC decided on names for the elements from 104 through 111. These eight elements are now called rutherfordium (Rf), dubnium (Db), sea-borgium (Sg), bohrium (Bh), hassium... 

Abstract In this chapter, the chemical properties of the man-made transactinide elements rutherfordium, Rf (element 104), dubnium, Db (element 105), seaborgium, Sg (element 106), bohrium, Bh (element 107), hassium, Hs (element 108), and copernicium, Cn (element 112) are reviewed, and prospects for chemical characterizations of even heavier elements are discussed. The experimental methods to perform rapid chemical separations on the time scale of seconds are presented and comments are given on the special situation with the transactmides where chemistry has to be studied with single atoms. It follows a description of theoretical predictions and selected experimental results on the chemistry of elements 104 through 108, and element 112. 

If rutherfordium (in this chapter, the element names endorsed in 1997 by the International Union of Pure and Applied Chemistry are used. Note that the names Kurchatovium (Ku) and... 

Of the transactinide elements, only the chemistry of rutherfordium and hahnium has been studied. These elements all have short half-lives and study of their chemical properties must occur at the accelerators where they are produced. Since typical production rates are such that the elements are produced one-atom-at-a-time, the experiments to deduce the chemistry of these elements must be carried out many times... 

A source of great controversy was the naming of element 106. U.S. chemists endorsed the name seaborgium, in honor of the U.S. chemist Glenn Seaborg, who, over his career, led teams of scientists that synthesized 10 new elements. No person has ever equaled this achievement, so the Americans were confident that their proposal for the name of element 106 would easily gain acceptance from the worldwide scientific community. To their dismay, however, the International Union of Pure and Applied Chemistry (lUPAC) endorsed the name rutherfordium, in honor of Ernest Rutherford (see Section 5.3), for element 106. Moreover, the U.S. chemists were shocked by the lUPAC proposal that element 104 be named dubnium in honor of achievements at the research laboratory in Dubna, Russia. There were serious douhts as to the validity of the Russian chemists data. 

Rutherford has been called the father of nuclear physics. His lifetime of accomplishments earned him the Nobel Prize in chemistry (not physics) in 1908, knighthood in 1914, the Order of Merit in 1921, and a place in the periodic table—element 104, rutherfordium (Rf). Soddy, an English chemist, received his own Noble Prize in 1921 for developing the concept of isotopes. 

Rutherfordium (Z = 104) cannot be produced directly in " Ca-induced reactions, as it would require a polonium target. The isotopes Rf (Jin. — 160 s) and Rf Ty2 — 1.3 h) are the terminating SF activities of the decay chains derived from and Fl, produced in " Pu(" Ca,xn) reactions with x = 5 and X = 3, respectively [8, 316, 353]. Rf activities produced in hot-fusion reactions with lighter heavy ions with much higher cross sections are generally more appropriate for radiochemical experiments (see Liquid-Phase Chemistry of Superheavy Elements and Gas-Phase Chemistry of Superheavy Elements ). However, the long half-life of Rf may provide the means for previously unexplored radiochemical investigations. 

It was emphasized in [1] that the nuclear decay properties of the isotope to be used in these studies must be well known and have unique decay characteristics suitable for detection and positive identification on an atom-at-a-time basis in order to verify that it is from the element whose chemistry is to be studied It must have a half-life comparable to the proposed chemical separation procedure as well as a reasonable production and detection rate to permit statistically significant results to be obtained, and must give the same results for a few atoms as for macro amounts. For the transactinide elements, production rates range from a few atoms per minute for rutherfordium (Rf, Z = 104) to only about one atom per day in the case of elements 108 (hassium, Hs), 112, and 114, the heaviest elements studied to date with chemical techniques. Details of these chemical investigations are outlined in Liquid-Phase Chemistry of Superheavy Elements and Gas-Phase Chemistry of SuperheavyElements . 

This chapter is divided into four parts. The first describes results of some previous experiments involving only a few atoms-at-a-time for actinides with Z > 100 and the transactinides, i.e., all elements beyond Z = 103, beginning with rutherfordium (Rf, element 104). The second deals with kinetic and thermodynamic aspects of the chemistry from tracer to single atom scale. The third, in an illustrative way, concerns experimental approaches. Finally, the effects of the media used and their influence on aqueous phase chemistry will be discussed. 

Abstract An overview over the chemical separation and characterization experiments of the four transactinide elements so far studied in liquid phases, rutherfordium (Rf), dubnium (Db), seaborgium (Sg), and hassium (Hs), is presented. Results are discussed in view of the position of these elements in the Periodic Table and of their relation to theoretical predictions. Short introductions on experimental techniques in liquid-phase chemistry, specifically automated rapid chemical separation systems, are also given. Studies of nuclear properties of transactinide nuclei by chemical isolation will be mentioned. Some perspectives for further liquid-phase chemistry on heavier elements are briefly discussed. 

The new elements should belong to the 6d transition elements beginning with element 104 (rutherfordium) for which a colorful chemistry is expected, quite different from the monotone chemistry of the preceding heavy actinides. Very little was known, however, about the chemistry of the transactinides. In aqueous solutions, cationic and anionic species of element 104 had been studied with standard column techniques [118, 119], and in the gaseous state, halide compounds of 104 and 105 by their volatilization and deposition on solid surfaces [120-122]. 

Chapter 6 presents the wealth of information obtained about properties of transactinides up to element 106, seaborgium, in the aqueous phase. This includes new and detailed information on the chemistry of elements 104, rutherfordium, and element 105, dubnium. 

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