Oct. 20, 1957
5583
COMNUNICATIONS TO THE EDITOR
in the large thermal gradient normal t o the surface of the hot filament We are confident of success in determining the atomic arrangement in rhombohedral boron when we shall have completed the quantitative measurement of the numerous h k I intensity data. Thanks are due Dr. Gordon S. Smith and Mr. D. B. Sullenger for taking some of the photographs. (8) S o w a t Radiation Laboratory, Universlty of Callfornla, Lirermore, California.
BAKERLABORATORY OF CHEMISTRY CORNELLUNIVERSITP DOXALD E. SASDS* J. L. HOARD ITHACA, NEW YORK RECEIVEDJULY 30, 1957 THE PREMIXED OZONE-CYANOGEN FLAME1n2
Sir: The pure ozone decomposition flame to oxygen3 and the premixed ozone-hydrogen flame4 were recently described. A premixed pure ozone flame with a carbon compvund, namely, cyanogen, has now been achieved. It was first established, in static experiments, that cyanogen and pure ozone can be mixed and stored for a considerable time without reaction. Thus the mixture 3(CN)2 4 0 3was kept in a 100% 0 ATOMS [ O F TOTAL NUMBER OF ATOMS P R E S E N T ] , cc. Pyrex vessel, a t 1000 mm. at 0' for 2.0 hours Fig. 1.-Burning velocities of 0 8 (CN)? and 0 2 with no noticeable change in pressure; after this (CN)Z mixtures ( a t 0" initial gas temperature and 1 atm.). time cyanogen was frozen out at -78", the 0 3 All flames on the (CN)z-rich side up to and inpumped off and the volumes of the separated gases N t burn were found to be essentially equal to their original cluding the mixture burning to 2CO volumes. Identical results were obtained with uniformly, noiselessly, as brightly as an electric arc 0 3 and with a pink-violet color. The 2(CN)2 the mixture 3(CN)2 203. The results of our laminar flame measurements flame is particularly bright and has a different are given in Fig. 1 and compared with 02. Burn- characteristic blue green color. Their temperatures can be calculated6 with great ing velocities of (CN)2-03mixtures containing 2.5.0, 33.3, 40.0 and 100.0 mole % 0 3 were, respec- accuracy ( + 2'K.) ; one of them is compared with 3, 242 12, 285 =t G and 420 + 6 the corresponding O2flame's8 below tively, 60 cm./sec. A mixture beyond the stoichiometric 7 0 D . - - Gas 1.o 10.0 point, on the Oa-rich side, containing 50.0 atom 7 0 composition Atm. Atm. 0 detonated immediately upon ignition. The (CX), On 4850 5025 same apparatus was used as in the 03-Hz measure3(CX)* 4- 20, 5208 3506 m e n t ~ ~the ; desired mixture was stored over water in a Pyrex gas holder, dried by passing through a In these calculations the value of AIIfZ5Ofor ozone trap cooled t o -19'. (H20-content of gas = = 3-33.98. and for cyanogen = +73.85 kcal.,'mole 0.11 mole yo)and ignited by a hot Pt-wire from an was used. aluminum burner tip ( i d . = O.6G nini.). Since (F) Acknowledgment is made t o t h e Reaction Motors, Inc., and flame velocities of (CN)2-0z flames are increased t o Mrs. Marianne Stoltenberg for their help n i t h some of the calculaby traces of H20,jwe used the same apparatus and tions. (7) J. B. Conway, R. H. Wilson, Jr., and A. V. Grosse, THISJ O U R the same conditions t o measure (CN)2-0zflames. 76, 409 (1953). The shapes of the three O3 flames described are NAL, ( 8 ) J. B. Conway, W. F.R . Smith, W. J. Liddell and A. V. Grosse, widely d i f f e r e r ~ t . ~Although .~ the Os-rich side of ibid., 77, 2026 (19%). the Oa-H2 and (CN)z-03 systems could not be ex- THERESEARCHISSTITUTE A. G . STRETG plored due t o their detonability, it is unlikely that OF TEMPLE USIVERSITY -1, 1'. GROSSE 44, P.4. the latter system will show the high peak of the PHILADELPHIA RECEIVED XVGUST 26, 1957 03-H~system. -111 (CI%),-03 mixtures burn comparatively slowly and even a t the 2CO+N2 ( k , = 33.3 atom % 0) point, the velocity is substanDERIVATIVES OF I-THIA-4,s-DIAZACYCLOHEPTAtially below that of pure ozone. 2,4,6-TRIENE. 111. CORRECTIONS AND ADDENDUM
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(1) Paper presented a t t h e Sixteenth International Congress on Pure and Applied Chemistry, Paris, France, July 18-24, 1957. (2) This research was supported by t h e United States Air Force through t h e Air Force Office'of Scientific Research of t h e Air Research and Development Command under Contract h-0. AF-l8(600)-1175. ( 3 ) .4. G. Streng and . I v. .Grosse, THISJ O u R N n r . . 79, 1317 (1957). (1)A. G. Streni: and h 1'. Grosse, ibid., 7 9 , in press (1057). ( 5 ) 12. S. Prokaw and I
