Measurement of hyperfine field in mavicyanin by perturbed angular correlation of gamma-rays

Perturbed angular correlation of gamma-rays (PAC) is a powerful method to investigate hyperfine fields in a molecule in liquid state based on nuclear electric quadrupole interactions. Taking advantage of the method, it is interesting to measure the hyperfine field at a metal site of biological molecule in an aqueous solution as functioning in life. In this study, the structure around the metal site of Mavicyanin, a protein molecule with a copper site, was investigated by using time-differential PAC of 117In. Its parent nuclide 117Cd decays by beta emission to populate the 749 keV excited state of 117In with a half-life 2.49 h, decaying to the 315 keV excited state through the 660 keV intermediate state having a spin I = 3/2, t1/2 = 53.6 ns, and an electric quadrupole moment Q = (-)0.59(1) b. (orig.)