This table is a compilation of experimental values of magnetic hyperfine anomaly in atomic and ionic systems. The last extensive compilation was published in 1984 by Buttgenbach (Hyperfine Interactions 20, (1984) p 1) and the aim here is to make an up to date compilation. The literature search covers the period to January 2011

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A new method for extracting the hyperfine anomaly from experimental hyperfine structure constants is suggested. Instead of independent high-precision measurements of the nuclear magnetic dipole moment, precise measurements of magnetic dipole hyperfine interaction constants for two atomic states and a theoretical analysis can be used. This can lead to determination of hyperfine anomaly for radioactive isotopes where the nuclear magnetic dipole moment is not known with high accuracy. PACS. 31.30.Gs Hyperfine interactions and isotope effects -21.10.Ky Electromagnetic momentsThe influence on the hyperfine structure (hfs) of the finite size of the nucleus was considered by Bohr and Weisskopf [1]. They calculated the hyperfine interaction (hfi) of s 1/2 and p 1/2 electrons in the field of an extended nucleus, and showed that the magnetic dipole hfi constant a for an extended nucleus is generally smaller than that expected for a point nucleus. Isotopic variations of magnetic moments become larger than those in the point dipole interaction when there are different contributions to the hfs from the orbital and spin parts of the magnetisation in the case of extended nuclei. The fractional difference between the point nucleus magnetic dipole hfi constant and the constant obtained for the extended nuclear magnetisation is commonly referred to as the Bohr-Weisskopf (BW) effect [2]. The magnetic dipole hfi constant a can therefore be written aswhere BW is the BW-effect, and a point the a constant for a point nucleus. Because electronic wavefunctions cannot be calculated with high accuracy in complex atoms it is not possible to determine BW directly; only the difference of the BW-effect in two isotopes, the so-called hyperfine anomaly (hfa), can be determined experimentally. Therefore one compares the ratio of the measured hfs constants for two isotopes (or isomers) of the same element with the independently measured ratio of the nuclear magnetic dipole moments to extract the hfa, 1 ∆ 2 , for the isotopes 1 and 2, and a given atomic state:

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A chemistry concept inventory (Chemical Concept Inventory 3.0/CCI 3.0) has been developed for assessing students learning and identifying the alternative conceptions that students may have in general chemistry. The conceptions in question are assumed to be mainly learned in school and to a less degree in student's daily life. The inventory presented here aims at functioning as a tool for adjusting teaching practices in chemistry and is mainly designed for assessing the learning outcome during university general chemistry courses. Used as a pre-test the inventory may also give information about student's starting point when entering university's first year chemistry courses.The inventory also aims at functioning as a tool for adjusting teaching practices in chemistry. It has been administered as a pre-and post-test in general chemistry courses at the Norwegian University of Science and Technology (NTNU), and evaluated using different statistical tests, focusing both on item analysis and the on the entire test. The results indicate that the concept inventory is a reliable and discriminating tool in the present context.

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