The Kuo interaction and band shifts in the sd-shell

Evidence is presented to show that the major defect of the Kuo interaction in untruncated shell-model calculations in the sd-shell is that it produces shifts of whole rotational bands relative to one another, the calculated spacings within the bands being well reproduced even where they do not follow the J(J + 1) rule. The results of calculations in ²³Na, ²⁴Na, ²⁶Al and ³³P are used as illustrations.