The Continuous Absorption of Oxygen Between 1750 and 1300A and Its Bearing Upon the Dispersion

Vacuum-Ultraviolet-Induced Oxidation of Polyethylene

“…Molecular oxygen absorbs between 135 and 170 nm,9 dissociating into a ground state (03P) and an excited (01D) atom. 10 Consequently, radiation of wavelengths 112 < < 135 nm and > 170 nm can arrive at the polymer surface essentially unattenuated. By combining knowledge of the plasma emission (Figure 1) and of the transmission characteristics, we are able to carry out three types of experiments:…”

Spectroscopy of Organic Molecules in the Vacuum Ultraviolet

“…If e"is known throughout the region covered by an electronic band, it may be used to compute the oscillator strength of the transition, v is in cm ' and D is in A'). The quantity f is the same as the oscillator strength which appears in the classical dispersion equation; this identity has been strikingly proved for 0& by the vacuum absorption measurements of Ladenburg and Van Voorhis(146).The values of f and D may also be obtained theoretically from the relation D = GQ' where Q =~P '(P; r, ) P"dr, if suitable approximations for the wave functions of the electrons. can be found.…”

“…The usual kind of sector disk is too bulky for use in a small vacuum system, although a compact variant has been devised for this purpose (147). Ladenburg (146) obtained an intensity calibration by placing symmetrical sector-shaped diaphragms over their condensing lenses in front of the spectrograph slit; this method assumes that the effective light intensity is properly distributed across the aperture. The use of calibrated wire screens in a similar way has been suggested (144), but does not seem to have been actually tried as yet in this region.…”

Opacity

“…The reflection technique corresponds to assuming a delta function dependence on the internuclear separation, R, for the vibrational wave function of the upper state (Winans and Stuckelberg 1928). The normalization is fixed by requiring R 1 0 d Q D constant (i.e., independent of T ), which corresponds to Ladenburg 1914and 1921, Ladenburg and van Voorhis 1933, and compare with Thomas-Reiche-Kuhn sum rule in section "The Polarization Propagator Method" in Sect. 5.3.3).…”