EPR OF RADIATION-DAMAGE CENTERS W11, W12, W13 AND W14 IN TYPE IB DIAMOND

W11, W12, W13 and W14 are four paramagnetic defects with S = 3/2 obser ved in electron or neutron irradiated type Ib diamonds. Although spin Hamiltonian parameters have been determined that describe the ESR resu lts very well, it will be shown that the normal spin the normal spin H amiltonian with S = 3/2 is not entirely sufficient to describe the ang ular dependence of the ESR spectra. Possible tentative models for the defects will be discussed.