In January 2017 yet another revised version of the data booklet became available. However there is still a real problem with the atomic radii given for the elements in Groups 1, 2 and 13.The images below show how the values for Groups 1 and 2 have changed from the data booklet used for the previous programme. The table on the left is from Section 9 of the current 2016 data booklet whereas the table on the right is from...