A large number of data points for the vibrational relaxation time (ptgr;vin atm sec) of simple systems have been logarithmically plotted vs (Tdeg;K)mdash;frac13;. It appears that each system is well represented by a straight line, and that most of these straight lines when extended to higher temperatures intersect near the point ptgr;v=10mdash;8atm sec, (Tdeg;K)mdash;frac13;=0.03. Systems with a small reduced mass mgr; are exceptions to such a simple convergence, and in an improved scheme, the location of the convergence point is dependent on the reduced mass. Such a presentation has lead to an empirical equation correlating available measurements of vibrational relaxation times:log10lpar;ptgr;vrpar;equals;lpar;5.0times;10minus;4rpar;mgr;12thgr;43lsqb;Tminus;13minus;0.015mgr;14rsqb;minus;8.00, where thgr; is the characteristic temperature of the oscillator in K deg. This equation reproduces the measured times within 50 for systems as diverse as N2, I2, and O2sngbnd;H2. In the worst case thus far, O2sngbnd;Ar near 1000deg;K, it is off by a factor of 5.
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