Mutation in impact factor

摘要

Acta Crystallographica Section A: Foundations of Crystallography [pISSN 0108- 7673] exhibited perhaps the first ever mutation in the impact factor (IF) of a journal. Specifically, its IF was merely 2.051 in 2008, mutated to 49.926 in 2009 and even increased to 54.333 in 2010; now its 2011 IF is 2.076, i.e. what it should have been 1 . The main reason attributed to this high IF was a single paper authored by George Sheldrick, ‘A short history of SHELX’ (2008, 64A, 112–122) providing an account of the development of the SHELX system of computer programs from 1976 to date 2 .