Electric quadrupole moments of the first excited states of 194Pt, 196Pt and 198Pt

Coulomb excitation of 194,196,198Pt by 4He, 12C and 16O projectiles has been used to determine the static electric quadrupole moments Q(21+) of the first excited states of 194,196,198Pt, together with values of B(E2; 01+→21+). It is clearly established that Q(21+) is positive for each nucleus, having values of 0.48 (14)e . b and 0.66 (12)e . b for 194Pt and 196Pt, respectively, and 0.42 (12)e . b or 0.54 (12)e . b for 198Pt, depending on whether the interference term P4(22+) is positive or negative. Results obtained for B(E2; 01+→21+) are 1.661 (11)e2 . b2, 1.382 (6)e2 . b2 and 1.090 (7)e2 . b2 for 194,196,198Pt, respectively. The results are compared with the predictions of various nuclear models. (orig.)