Herak J N, Sankovic K, Hütterman J
Department of Pharmacy and Biochemistry, University of Zagreb, Croatia.
Int J Radiat Biol. 1994 Jul;66(1):3-9. doi: 10.1080/09553009414550891.
Single crystals of cytosine hydrochloride with thiocytosine as an impurity were found suitable for the study of a possible new mechanism of long-range migration of energy deposited by ionizing radiation. In a crystal containing thiocytosine, two kinds of chlorine-containing paramagnetic centres are present that are completely absent in the pure cytosine. HCl crystals irradiated under the same condition. The thiocytosine molecules in conjunction with Cl- ions behave as hole traps. The centres have been characterized by EPR spectroscopy. One of the centres is derived from the cationic thiocytosine radical by interaction with a Cl- ion, and the other centre is formed by interaction of Cl. with a thiocytosine molecule. It is suggested that the transfer of an electron-loss site (a hole) in the Cl- network is the actual mechanism of the long-range energy transfer.
发现含有硫代胞嘧啶作为杂质的盐酸胞嘧啶单晶适用于研究电离辐射沉积能量的远程迁移可能的新机制。在含有硫代胞嘧啶的晶体中，存在两种含氯顺磁中心，而在纯胞嘧啶中则完全不存在。在相同条件下辐照HCl晶体。硫代胞嘧啶分子与Cl-离子结合充当空穴陷阱。这些中心已通过电子顺磁共振光谱进行了表征。其中一个中心是由阳离子硫代胞嘧啶自由基与Cl-离子相互作用产生的，另一个中心是由Cl与硫代胞嘧啶分子相互作用形成的。有人提出，Cl-网络中电子损失位点（空穴）的转移是远程能量转移的实际机制。
