Isotopes of lithium

One of the most obvious features of Figs. 1.1 and 1.5 is the very low cosmic abundance of the stable isotopes of lithium, beryllium and... 

ISOTOPES There are two stable lithium isotopes Li-6.015, which makes up 7.5% of all lithium atoms, and Li-7.016, which makes up 92.5% of lithium atoms found in the Earth s crust. Less prevalent isotopes of lithium are Li, Li-5, Li-8, Li-9, Li-10, and Li-11. They are unstable with short half-lives and make up only a very small fraction of Lithium s total averaged atomic weight. 

The expected advantages of the proposed experiment are of three kinds. First, this experiment will operate on isolated atoms, thus avoiding all possible parasitic effects related to macroscopic samples. Second, its sensitivity is expected to be at least comparable and hopefully larger than the one achieved by the best previous experiments reported below. Third, one can perform the experiment with the two natural isotopes of lithium, 6Li and 7Li and comparing these two results will lead to an independent measurement of neutron charge. 

An interesting feature of our experimental scheme is that it could also be used for the 6Li isotope. Since the resonance spectra of both isotopes of lithium are not very different, one would only need a small change in the tuning of lasers. Comparison between 7Li and 6Li results would then provide an independent limit on neutron charge. 

Natural isotopes of lithium and their solar abundances... 

Tritium is made artificially in a nuclear reactor by the reaction of the light isotope of lithium with neutrons ... 

Fujii, Y. et al., Separation of isotopes of lithium and uranium by electromigration using cation-exchange membranes, Isotopenpraxis, 15, 7, 203, 1979. 

Two namrally occurring isotopes of lithium exist lithium-6 and lithium-7. Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the right of the element s name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. 

In addition, five radioactive isotopes of lithium have been produced. A radioactive isotope is one that breaks apart and gives off some form of radiation. Radioactive isotopes are produced when very small particles are fired at atoms. These particles stick in the atoms and make them radioactive. None of these isotopes has any important commercial application. 

The Affective Disorders Manic Depressive Psychoses Lithium in the Affective Disorders A. Side Effects Chemistry Isotopes of Lithium Inorganic Biochemistry Mechanisms of Action Lithium and the Phosphoinositide Signaling System Lithium and the Cell Membrane A. Sodium-Lithium Exchange Anion Exchange Leak... 

Lithium occurs naturally as a mixture of the two stable isotopes Li (7%) and Li (93%). Until recently these have not been readily distinguished. We have developed a technique for the identification and estimation of the two stable isotopes using AAS techniques and have applied this to a pharmacokinetic study in humans (70). In a parallel study, Thellier, using neutron activation to measure Li in biological samples, has shown that lithium accumulates in the less well-myelinated areas of the central nervous system. The technique was extended to study the tissue transport of the two stable isotopes of lithium (71). 

The atomic weight of lithium is 6.941 amu. The two naturally occurring isotopes of lithium have the following masses Li, 6.01512 amu Li, 7.01600 amu. Calculate the percent of Li in naturally occurring lithium. 

All neon isotopes have ten protons and ten electrons. Ne-20 has ten neutrons Ne-21 has 11 neutrons and Ne-22 has 12 neutrons. Look at the isotopes of lithium in Figure 2.11. The properties of the common subatomic particles are summarized in Table 2.1. 

Isotopes are identified by placing the mass number after the name or symbol of the element. The two isotopes of lithium are Li-7 and Li-6. ... 

There are two naturally occurring isotopes of lithium, f Li and l Li. Calculate the atomic mass of lithium as it would appear on the periodic table. 

PI. Perret, L., L. Rozand, and E. Saito Investigation of the Separation Coefficient of Certain Processes Involving the Isotopes of Lithium, PICG(2j 4 595 (1958). 

Isotope shifts for the various isotopes of lithium Li to Li have been measured by the group of Kluge et al. at GSI (including a collaboration with TRIUMF for Li) and the results reported in Refs. [66,65]. The result for Li is of special interest because, like He, it is a halo nucleus with a Li core, and so the nuclear radius is very sensitive to the details of nuclear structure. All the experiments involve measurements of the isotope shift for the 2 Si/2-3 Si/2 two-photon transition. As an interesting test of the method. Table 4.9 compares theory and... 

In theory, diffusion coefficients can be measured for any ion. In practice, however, most studies of ionic diffusion in glasses have been restricted to highly mobile ions which have a convenient radioactive isotope for use in tracer measurements. As a result, a majority of the data for ionic diffusion deals with sodium, with lesser amounts of data for potassium, rubidium, and cesium. Studies of lithium are very limited due to the lack of a radioactive isotope of lithium, while studies of divalent and other, more highly charged, ions are restrieted by the very low mobilities of these ions as compared to those of the monovalent ions. 

INTERPRETING GRAPHICS Examine Figure 1.2, and predict whether 3 Li is a stable isotope of lithium. Explain your answer. 

Because of the low values of the quadrupole moments for both isotopes of lithium, dipolar relaxation becomes important. In aqueous solution at ambient temperature dipolar relaxation accounts for over 75% of the relaxation of Li (T - 20 s) and almost 100% of Li (T -170 s). In D2O solution with no H available for dipolar relaxation and virtually no quadrupolar mechanism available, the relaxation time of Li becomes very long (T - 830 s). In contrast, it appears that despite the low quadrupole moment of Cs, dipolar relaxation does not contribute significantly. 

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