Evidence for a nuclear hexadecapole interaction in the hyperfine spectrum of Lil

摘要

The molecular beam electric resonance technique has been used to examine the hyperfine spectrum of ~7LiI to determine the nuclear hexadecaplole interaction of the iodine nucleus. The nuclear magnetic octupole interaction was also considered but found to be marginally significant. A total of 172 transitions in vibrational states 0-3 and rotational states 1-6 have been included in a fit to determine the iodine nuclear quadrupole, spin-rotation, and hexadecapole interactions, the lithium quadrupole and spin-rotation interactions, and the tensor and scalar parts of the spin-spin interaction. Vibration and rotation dependencies of these constants have been determined. The results include: eHh = -0.0151(30), eQ_Iq_I = -194351.212(17) - 8279.521(46)(v + 1/2) + 100.616(34)(v + 1/2)~2 - 0.3949(73)(v + 1/2)~3 - 6.41977(50)J(J + 1) + 0.10593(33)(v + 1/2)J(J + 1), eQ_(Li)q_(Li) = 172.613(52) - 3.26(14)(v + 1/2) + 0.00145(87)J(J + 1), c_I = 6.80260(32) + 0.00303(49)(v + 1/2) - 0.000118(13)J(J + 1), c_(Li) = 0.75872(72) - 0.0088(11)(v + 1/2), c_3 = 0.62834(68) - 0.0050(11)(v + 1/2), c_4 = 0.06223(36) + 0.00041(26)(v + 1/2), and e#OMEGA#_I#omega#_I = 0.000112(73), all in kHz with one standard deviation uncertainties for the last 2 digits in ().