Book Description

After the 1973 report on the fundamental constants by Cohen and Taylor, a new measurement of Avogadro's constant, (N sub A), was published by Deslattes et al. Based on improved techniques, the result is considerably more precise than the 1973 value, which was based primarily on other types of data, and is 8.2 ppm (1.6 times the 1973 standard deviation) larger. In the present report, a new least-squares adjustment is made, with six parameters and using the measurement of (N sub A) plus other new data. Recommended values of 75 constants are presented, half of which differ from the former values by 1.0 to 1.5 times the 1973 standard deviation. The uncertainties of the new values are often much less than the 1973 uncertainties, 0.38 as large according to one figure of merit.