Transactinide chemistry

From the general equations of P and Z, we will focus on the case of a single microcomponent involved in a reaction of stoichiometry 1-1, which is the only case encountered in transactinide chemistry. The Equation 2 reduces to ... 

Speciation Due to the fact that transactinide nuclei are detected after chemical separation via their nuclear decay, the speciation cannot be determined. Currently, the speciation in all transactinide chemistry experiments has to be inferred by carefully studying the behavior of lighter, homologue elements. The chemical system must be chosen in such a manner that a certain chemical state is probable and stabilized by the chemical environment. 

Atoms of the transactinide elements are produced at extremely low rates atoms per minute for Rf and Db, down to atoms per day for elements 106-108. They are produced among much larger amounts of background activities which hinder the detection and identification of decay of the transactinide atoms of interest. For these reasons, there is a recognized need for a physical pre-separation of the transactinide element atoms before chemical separation. Thus, it has been proposed that a kinematic separator could be coupled to a transactinide chemistry system with an aerosol gas-jet device, and a workshop has been held to discuss the merits and design of such a device [33],... 

This robotic sample preparation and counting technology, together with mechanical improvements in the chemical separation system, has resulted in an automated column chromatography system that can run almost autonomously, whereas several people were required to operate the ARCA II system for a transactinide chemistry experiment. 

Transactinide chemistry experiments with Rf have been carried out with the AIDA apparatus [59],... 

In transactinide chemistry research, gas phase separation procedures play an important role. Already, the very first investigation of rutherfordium has been conducted in form of frontal isothermal gas chromatography in a chlorinating atmosphere [1]. The success of gas chemical separations in transactinide research is quite remarkable since gas chromatography is, in general, of minor importance in inorganic analytical chemistry. 

Nuclides from nuclear fusion reactions used in transactinide chemistry... 

The general equations of partition function and canonical distribution have been applied to a reaction of stoichiometry 1—1, which is the case encountered in transactinide chemistry. Guillaumont et al. demonstrated that only in this case, the law of mass action holds, regardless of the number of present species, if the mean concentrations are used. However, when less than hundred atoms are involved in a reaction with a stoichiometry different from 1—1, deviations from the law of mass action can occur. For instance, in highly diluted solution, disproportionation of Pu(IV) and oxidation of U(TV) with Fe(lll) have been proved to display an erratic behavior with respect to the law of mass action. Thus, there is no general solution to describe the average populations when few atoms participate in a chemical reaction with a stoichiometry different from 1—1 [4, 5]. 

Ink-jet techniques. Piezoelectric pulsed drop jet devices have been used for target production [29]. These devices are similar to those used in ink-jet printers. So far, they have not been applied in transactinide chemistry experiments. 

Even, J. Developments for transactinide chemistry experiments behind the gas-filled separator TASCA. PhD-thesis. Universitatsbibliothek Mainz (2011)... 

Krebs, Robert E. The history and use of our earth s chemical elements a reference guide. Westport (CT) Greenwood P, 1998. ix, 346p. ISBN 0-313-30123-9 A short history of chemistry — Atomic structure The periodic table of the chemical elements — Alkali metals and alkali earth metals - Transition elements metals to nonmetals — Metallics and metalloids - Metalloids and nonmetals — Halogens and noble gases - Lanthanide series (rare-earth elements) — Actinide, transuranic, and transactinide series... 

Dr. Darleane C. Hoffman of the Nuclear Science Division of the Lawrence Berkeley National Laboratory and Department of Chemistry at the University of California at Berkeley has written and presented several papers documenting her work and that of her team on the laboratory production of transactinide and actinide elements one-atom-at-a-time. She explains the difficulty of determining the chemistry of heavy elements How long does an atom need to exist before it s possible to do any meaningful chemistry on it Is it possible to learn anything at all about the reactions of an element for which no more... 

After several actinides and transactinides were discovered, a dilemma arose as to nomenclature for naming newly discovered elements. Generally, elements were named after deceased persons who had made some significant contribution related to the field of chemistry or physics, or the element was named after the country in which the element was discovered. 

As a branch of chemistry, the activities of nuclear chemists frequentiy span several traditional areas of chemistry such as organic, analytical, inorganic, and physical chemistry. Nuclear chemistry has ties to all branches of chemistry. For example, nuclear chemists are frequently involved with the synthesis and preparation of radiolabeled molecules for use in research or medicine. Nuclear analytical techniques are an important part of the arsenal of the modem analytical chemist. The study of the actinide and transactinide elements has involved the joint efforts of nuclear and inorganic chemists in extending knowledge of the periodic table. Certainly, the physical concepts and reasoning at the heart of modem nuclear chemistry are familiar to physical chemists. In this book we will touch on many of these interdisciplinary topics and attempt to bring in familiar chemical concepts. 

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. 

The chemical behavior of the transuranium elements is interesting because of its complexity and the insights offered into the chemistry of the lighter elements. The placing of these manmade elements into the periodic table (Fig. 15.1) represents one of the few significant alterations of the original periodic table of Mendelyeev. Since so little is known about the chemistry of the transactinide elements, one has the unique opportunity to test periodic table predictions of chemical behavior before the relevant experiments are done. 

Relativistic quantum chemistry of superheavy transactinide elements 243... 

Gaggeler, H.W. Chemistry of the Transactinide Elements . In Proceedings of The Robert A. Welch Foundation Conference on Chemical Research XXXIV. Fifty Years with Transuranium Elements , Houston, Texas, 22-23 October 1990, pp. 255-276. 

J.F., Constantinescu, M., Barci, V., Weiss, B., Gasparo, J., Ardisson G. Extended abstracts. 1 St International Conference on the Chemistry and Physics of the Transactinide Elements, Seeheim, September 26-30 (1999). Contribution PW-20... 

A chemistry experiment with a transactinide element can be divided in four... 

Extensive studies of chemical properties of transactinide elements, Rf, Db, and Sg have been performed with the Automated Rapid Chemistry Apparatus (ARCA), see summaries in Ref. [15, 44, 45]. To improve the speed and reduce cross contamination, the ARCA n was built, featuring two magazines of 20 miniaturized ion exchange columns [46]. With the large number of columns, cross contamination between samples can be prevented by using each column only once. By miniaturizing the columns, the elution... 

INSTRUMENTATION FOR EARLY GAS-PHASE CHEMISTRY EXPERIMENTS WITH TRANSACTINIDE ELEMENTS... 

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