No abstract

SYNOPSISThe marked change of the conductivity, the photoconductivity and the photo-e.m.f. is revealed when the poly-copperphenyl acetylenide (PAC) is treated by DNA, RNA and adenine. The spectral characteristics of the photoeffect, the sign of the charge carrier and kinetics of the photoconductivity are studied. The data obtained is explained by the creation of the new recombination centers after treatment of the PAC. The treatment of the polymer by amino acids leads to creating the complex copper (11) compounds and aminoacid residue. It is shown that the inner photoeffect in PAC can be spectrally sensitized up t o the near infra-red region after the dye adsorption on the polymer surface. The energy transfer mechanism is preferred for the explanation of the I.R. sensitization.Since 1960 we have been studying the inner photoeffect in organic polymers.'-6 Here we consider the alteration of the photosemiconductive properties of the poly-copper-phenyl-acetylenide (PAC) when the latter interacts with different agents.The paper consists of two parts. The influence of the nucleic acids (DNA and RNA), purine and pyrimidine bases and aminoacids on the semiconductive properties of the PAC is considered in the first section. This part of the study was initiated by the widespread ideas of semiconductor physics for investigation of the biopolymers and polypeptides 7-9 and nucleic acids.' O-' This proceeded from the notion about the important role of the charge transfer for oxidation processes in living organisms.' The analysis of the interaction of the synthetic polymers with biopolymers leads us, it seems, to the perspective of clearing the specific properties of the biological substances. The absence of the new bands in the photoconductivity spectra of the PAC, after its treatment with biopolymers, permits us t o consider the revealed phenomena as chemical sensitization of the photoeffect. The second part of the paper is related to the investigation of the spectral sensitization of PAC by adsorbed organic dyes. The effect of the spectral sensitization of the photoeffect in organic polymers for the visual range 0 1970 by John Wiley & Sons, Inc.

No abstract

A significant inner photoeffect in organic polymers with triple bonds R+CCR1CC+nR, and the metal polyacetylenides RCCM has been found and investigated by means of direct‐current photoconductivity and photoelectromotive force in intermittent light. The dependence of the photocurrent on the light intensity can be expressed by the equation iph ≐ αLn, where 0.5 < n < 1. The photocurrent relaxation in the range of 10−5 sec. to several minutes displays a second‐order process. Ohm's law is not obeyed. The absorption spectra have been compared with those of photoconductivity, photoelectromotive force, and luminescence. Preliminary short‐ultraviolet irradiation increases the photosensitivity; this is ascribed to bond rupture and electron‐trapping. The latter is confirmed by ESR measurements. Upon evacuation the dark conductivity and the photoconductivity are increased by 3 and 2 orders of magnitude, respectively, and the photoelectromotive force by 5. Oxygen and water vapor reversibly depress the dark and photoconductivity. A photodesorption of oxygen from the surface of metal polyacetalinide can be surmised. Electron acceptors (quinone, chloranil) and mercury vapor have a significant influence on the semiconduction. The photoeffect in the polymers can be spectrally sensitized by various adsorbed dyes. The proper sensitivity is equally changed on dye adsorption. The mechanism of the effects observed is discussed.

No abstract