Mallik B, Jain K M, Misra T N
Biochem J. 1980 Sep 1;189(3):547-52. doi: 10.1042/bj1890547.
On adsorption of some electron-acceptor molecules on the solid films of all-trans-beta-carotene, beta-apo-8'-carotenal, astacene and methylbixin a new absorption band appears on the longer-wavelength side of the spectrum in addition to the original bands. The position of this new band is dependent on the electron affinity (EA) of the acceptor molecules, and the intensity of this band increases with the amount of adsorbed acceptor molecules. A linear relationship between the vmax. of the new band and EA was observed. The value of the ionization potential of the polyenes estimated from such linear relationship agrees satisfactorily with the value obtained by other methods. It has been concluded that the polyenes behave as electron donor and first form molecular charge-transfer complexes (of type [polyene . I2] with iodine) with electron acceptors, these finally dissociating to yield ionic complexes (of type [polyene . I+] with iodine).
当一些电子受体分子吸附在全反式β-胡萝卜素、β-阿朴-8'-胡萝卜醛、虾青素和甲基胭脂树素的固体薄膜上时，除了原来的吸收带外，光谱的长波长侧还会出现一个新的吸收带。这个新吸收带的位置取决于受体分子的电子亲和势（EA），并且该吸收带的强度随着吸附的受体分子数量的增加而增强。观察到新吸收带的最大波数（vmax）与EA之间存在线性关系。通过这种线性关系估算的多烯的电离势值与通过其他方法获得的值令人满意地相符。可以得出结论，多烯表现为电子供体，首先与电子受体形成分子电荷转移络合物（如与碘形成的[多烯·I2]型），这些最终解离产生离子络合物（如与碘形成的[多烯·I+]型）。
