Thank you for bringing to my attention the recent International Union of Pure & Applied Chemistry report “Atomic weights of the elements 2009” (C&EN, Dec. 20 ...

COMPARISONS between the results of accurate quantum-mechanical calculations on atoms and molecules have been made unnecessarily complicated and sometimes even impossible by the lack of an agreed and ...

For the first time those little numbers that appear beneath some of the commonest elements in the periodic table boxes are about to change from a single value to an interval of numbers An ...

Nineteen elements on the periodic table — including gold, cadmium, arsenic and aluminum — are getting their atomic weights adjusted. The International Union of Pure and Applied Chemistry (IUPAC) ...

High-precision measurements of the mass of the deuteron, the nucleus of heavy hydrogen, provide new insights into the reliability of fundamental quantities in atomic and nuclear physics. This is ...