Photosynthesis in the Shortest Ultraviolet 139 



on silicates are also decomposed in the range of A < 2300 Â, rather than in the 

 Schumann ultraviolet. The easier photolysis of water molecules in these hetero- 

 geneous conditions is explained by the fact that water forms at the surface of 

 porous silicates, aluminosüicates and oxides superficial hydrates of the type 



I 

 — Si— OH, as observed by us in infra-red spectra [12], The splitting of OH 



I 

 radicals from these hydrates requires quanta of lesser magnitude than does the 



photodissociation of gaseous water, as has been found by us recently [13]. 



This shift of the photochemically sensitive spectral range toward longer 

 ultraviolet wavelengths, amounting to ca. i eV, or more than 20 kcal in energy, 

 results in the accessibility of the photoreactions of these inert gases to the 

 ordinary ultraviolet range, when they are adsorbed. This circumstance probably 

 explains that puzzling fact that in early experiments done during the first decade 

 of this century [14] it was found that water could be decomposed and even 

 formaldehyde photosensitized from carbon monoxide and water in quartz 

 vessels imder irradiation by an ordinary mercury quartz lamp in which the 

 wavelengths required to start this process (in unperturbed molecules) were 

 cerainly lacking. 



On summarizing my report, I consider it to be proved that aldehydes and 

 amino acids could be formed from the gases of the primitive Earth atmosphere 

 under the action of the shortest ultraviolet radiation of the sun. It is also likely 

 that in heterogeneous environment such photosynthesis was possible in the 

 longer ultraviolet range. 



REFERENCES 



1. C. DE Jager, Ann. Géophys., ii, 330, 1955, Table i; Usp.fiz. Nauk, 61, 653, 1957. 



2. P. Harteck & F. Oppenheimer, Z. phys. Chem. B 16, 77, 1932 j W. Groth, Z. Elektro- 



chem., 45, 262, 1939; W. Groth, Z. Elektrochem., 58, 752, 1954^ W. Groth & 

 Scharfe, Z. phys. Chem. (Frankf. Ausg), i, 300, 1954; 2, 142, 1954. 



3. P. A. Leighton & A. B. Steiner, J. Amer. chem. Soc, 58, 1823, 1936. 



4. H. Neuimin & A. Terenin, Acta phys.-chim. U.R.S.S., 5, 465, 1936; Izv. Akad. 



Nauk S.S.S.R. {cl. sc. math., natur.), 529, 1936. 



5. W. Groth, Z. phys. Chem., B 37, 307, 315, 1937; K. Faltings, W. Groth & P. 



Harteck, Z. phys. Chem., B 41, 15, 1938; K. Faltings, Ber. dtsch. chem. Ges., 72, 

 1206, 1939. 



6. W. Groth, Z. phys. Chem., B 38, 366, 1938. 



7. W. Groth & H. Suess, Naturwissenschaften, 26, 77, 1938. 



8. H. J. Emeleus, Trans. Faraday Soc, 28, 89, 1932. 



9. A. V. Jakovleva, Sow. Phys., 9, 547, 1936; Izv. Akad. Nauk S.S.S.R. (ser. fiz.), 



4, 59, 1940; I. I. Gromova, Optics & Spectr., i, 433, 1956; Trans. Xth Conf. on 

 Spectroscopy, Lvov, 1956 [Ed. Lvov Univ., 1957], p. 308. 



10. W. Groth & Hamis v. Weyssenhoff, Naturwissenschaften, 510, 1957. 



11. K. Kassparov & A. Terenin, Acta phys. chim. U.R.S.S., 15, 348, 1941. 



12. Cf. review: A. N. Terenin, Microchim. Acta, H. 2-3, 467, 1955. 



13. Cf. review: A. N. Terenin, in the Symposium Problems of Kinetics and Catalysis VIII, 



Ed. Acad. Sei. U.S.S.R., 1955, pp. 27-30. 



14. D. Berthelot & H. Gaudechon, C.R. Acad. Sei., Paris, 150, 1690, 1910; M. Kern- 



BAUM, C.R. Acad. Sei., Paris, 149, 273, 1909; A. Coehn, Ber. dtsch. chem. Ges., 43, 

 880, 1910; A. Coehn & Grote, Nernst Festschr., S. 136, 1912; A. Tian, Ann. phys., 

 Paris, 5, 248, 1916; J. Andrejew, Z. Electrochem., 19, 551, 1913. 



15. H. JucKER & E. K. RiDEAL, J. chem. Soc, 1058, 1957. 



16. Mei Chio Chen & H. A. Taylor, J. chem. Phys., 27, 857, 1957. 



