QUADRUPOLE-MOMENTS OF ISOMERIC STATES IN RA-212, RA-213 AND RA-214

The static-quadrupole-interaction frequency of the 8+ isomers in Ra-21 2 and Ra-214 and of the 2/17- isomer in Ra-213 has been measured with the level-mixing-spectroscopy (LEMS) method. Measurements have been pe rformed both at low and high target temperatures (10 and 420 K) and on polycrystalline as well as single-crystalline targets. Shell-model ca lculations have been performed to demonstrate the influence of configu ration mixing on the B(E2, 8+-->6+) values and the quadrupole moments of N = 126 isotones.