138 A. N. TERENIN 



bands belonging to such high excited levels of the N2 molecule, that they could 

 be reached only by subsequent absorption of light by metastable molecules [9], 

 These metastable nitrogen molecules, possessing an extraordinary large amount 

 of energy of 976 eV, must certainly display a definite chemical activity on 

 collisions with Ho, CH4, CO. 



From the indicated composition of the primary, intermediary and final pro- 

 ducts of the photochemical transformation of the natural gases here considered 

 it can be inferred that under favourable conditions from their combination not 

 only aldehydes and amides, but amino acids can also result. 



To test this possibihty experimentally we — at Leningrad University, and 

 independently Groth — at Bonn University [10], have tried to obtain the amino 

 acids from a mixture of ammonia, water vapour and methane*. He exposed to 

 Schumann radiation a mixture of CH4 and NH3 next to the surface of Hquid 

 water, and obtained a positive result : traces of glycine and of the alanines could 

 be detected by chromatography!. 



The conditions of our experiments differed from those of Groth in that respect, 

 that he used the radiation of a krypton lamp, i.e. the two strong lines 1235 and 

 1165 Â, whereas we had a powerful hydrogen lamp of a type described before 

 [4] with a many-lined and continuous spectrum in the Schumann range. The 

 spectral distribution of energy in the latter is nearer to that of the sun than the 

 separate monochromatic lines of the krypton source. 



The various reaction cells used allowed us to irradiate not only the gaseous 

 mixtures, but also layers of condensed gases frozen at low temperatures. This was 

 done in order that the primarily formed radicals should remain trapped, and 

 entered in subsequent reactions when the layer was warmed up. 



On exposing a mixture of CH4 + NH3 + CO and liquid water in contact 

 with these gases to the radiation of the hydrogen lamp through a thin LiF (or 

 CaF2) window, we detected by chromatography in the product the alanines and 

 several other amino acids, which latter could not be identified. The research is 

 still going on. 



In the presence of active adsorbents of the type of oxides there arises the 

 possibility of photoactivation of NH3 and H2O to the reaction with methane by 

 longer ultraviolet radiation (A > 1850 Â). This follows from the photodisso- 

 ciation of NH3 and H2O molecules observed by us when these molecules are 

 adsorbed on alumina, aluminosilicates and silicates. 



Upon adsorption of gaseous ammonia on active aluminium oxide the threshold 

 of its photolysis into nitrogen and hydrogen is shifted to considerably longer 

 wavelengths, viz. from 1900 Â to 2700 Â [11] (Fig. i)J. Water molecules adsorbed 



* The results have been reported by Groth at the last International Congress of 

 Chemistry in Paris in July 1957. 



t In his research Groth also tried the well-known photo-sensitization of the gas 

 reactions to the longer ultraviolet, viz. to the mercury resonance line 2537 A, which is 

 achieved by adding mercury vapour to the gas mixture. It is the former which is the photo- 

 active component. It was found that amino acids can also be detected in this case, not for 

 methane as component, but for ethane only. This method has however no connection 

 with the problem considered here. 



+ The horizontal bracket with the notation 'ads' on the figure represents this spectral 

 shift. 



