| Abstrakt: |
A careful search has been made, in systems exhibiting triplet mechanism electron spin polarization, for the predicted effects on the magnitude of the spin polarization of the orientation of the plane of polarization of the exciting light used to create the radicals. A variety of techniques, including two very sensitive new ones based upon lineshape analysis, has been used. No definite effect has been detected, although there is some indication of one below the 0·5 per cent level in one system studied, despite efforts to optimize its magnitude by careful choice of molecules and experimental conditions. This contrasts with both theoretical predictions and previous experimental reports. Despite the original proposal, observation of the effect, or lack of it, does not constitute an absolute test for the occurrence of the triplet mechanism as the source of single-phase electron spin polarization in solution. |
