Search results
Results from the WOW.Com Content Network
Isotopomers of isotopically modified ethanol. The molecule at the bottom left is not an isotopomer of any other depicted molecule. Isotopomers or isotopic isomers are isomers which differ by isotopic substitution, and which have the same number of atoms of each isotope but in a different arrangement.
A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state levels (higher energy levels). ). "Metastable" describes nuclei whose excited states have half-lives 100 to 1000 times longer than the half-lives of the excited nuclear states that decay with a "prompt" half life (ordinarily on the order of 10
A chart or table of nuclides maps the nuclear, or radioactive, behavior of nuclides, as it distinguishes the isotopes of an element.It contrasts with a periodic table, which only maps their chemical behavior, since isotopes (nuclides that are variants of the same element) do not differ chemically to any significant degree, with the exception of hydrogen.
The term isotopes (originally also isotopic elements, [4] now sometimes isotopic nuclides [5]) is intended to imply comparison (like synonyms or isomers). For example, the nuclides 12 6 C, 13 6 C, 14 6 C are isotopes (nuclides with the same atomic number but different mass numbers [6]), but 40 18 Ar, 40 19 K, 40 20 Ca are isobars (nuclides with ...
In physics, mirror nuclei are a pair of isobars of two different elements where the number of protons of isobar one (Z 1) equals the number of neutrons of isobar two (N 2) and the number of protons of isotope two (Z 2) equals the number of neutrons in isotope one (N 1); in short: Z 1 = N 2 and Z 2 = N 1.
The isomeric shift on atomic spectral lines is the energy or frequency shift in atomic spectra, which occurs when one replaces one nuclear isomer by another. The effect was predicted by Richard M. Weiner [2] in 1956, whose calculations showed that it should be measurable by atomic (optical) spectroscopy (see also [3]).
See Isotope#Notation for an explanation of the notation used for different nuclide or isotope types. Nuclear isomers are members of a set of nuclides with equal proton number and equal mass number (thus making them by definition the same isotope), but different states of excitation. An example is the two states of the single isotope 99 43 Tc
There are 28 known radioisotopes and 8 nuclear isomers, the most stable of which are 60 Fe (half-life 2.6 million years) and 55 Fe (half-life 2.7 years). Much of the past work on measuring the isotopic composition of iron has centered on determining 60 Fe variations due to processes accompanying nucleosynthesis (i.e., meteorite studies) and ore ...