Anna J. Harrison

The Far Ultraviolet Absorption Spectra of Simple Alkyl Amines

A quantitative study of the absorption spectra of ammonia, the three methyl and the three ethyl amines, has been made in the region 39 000 to 63 000 cm−1. Three electronic transitions have been observed in most cases. The first is of low intensity particularly in the secondary amines, the second is of higher intensity and increases from the primary to the tertiary compound, and the third, which is only partially covered by these measurements, is of intermediate intensity. The positions of all transitions, particularly the second, are influenced by alkyl substitution. These transitions are discussed in relation to the spectrum of ammonia. Vibrational structure, present in ethyl amine, methyl amine, and dimethyl amine, has been analyzed in part.

Absorption of Acyclic Oxygen Compounds in the Vacuum Ultraviolet. II. Ethers

A fluorite prism vacuum spectrograph and a hydrogen lamp have been used to determine the 45 000‐ to 65 000‐cm—1 absorption spectra of dimethyl ether, diethyl ether, divinyl ether, and 1,4‐pentadiene in the vapor phase at 22°C.

Effect of Ring Size on the Far Ultraviolet Absorption and Photolysis of Cyclic Ethers

Absorption curves, tabulated extinction coefficients, and oscillator strengths are given for trimethylene oxide, ethylene oxide, and formaldehyde vapor in the spectral range 2000–1550 A. A comparison is made of the spectra and photochemical stability of these compounds with those of previously determined five‐ and six‐membered ring ethers.

Absorption of Acyclic Oxygen Compounds in the Vacuum Ultraviolet. III. Acetone and Acetaldehyde

A fluorite prism vacuum spectrograph and hydrogen lamp have been used to determine the 49 000‐ to 67 000‐cm—1 absorption spectra of acetone and acetaldehyde in the vapor phase at 22°C.

Quantitative Determination of Extinction Coefficients in the Vacuum Ultraviolet: Divinyl Ether

A method of determining the molar extinction coefficients of organic compounds in the vapor phase in the vacuum ultraviolet has been developed. Measurements made with a fluorite spectrograph on flowing vapor samples of divinyl ether show a precision of 3 to 8 percent and satisfactory agreement with measurements made from 2360 to 2100A with a Beckman DU spectrophotometer. The absorption spectrum of divinyl ether is completely free from fine structure. The extinction coefficient increases rapidly from a value of 10 at 42,400 cm−1 to a maximum of 15,900 at 49,200 cm−1 and decreases to a minimum value of 4000 before beginning to rise again at 56,700 cm−1. The oscillator strength of the band is 0.45.

Common Elements and Interconnections

The major concepts addressed in this article are the synergistic nature of science, engineering, and technology; the benefits and burdens of technology; the resolution of societal issues; and the roles of scientists and engineers in the resolution of societal issues.

Absorption Intensities of the Isomeric Pentenes in the Vacuum Ultraviolet

Quantitative measurements of the absorption spectra of the six isomeric pentenes in vapor phase have been made in the region 45 000—65 000 cm—1. The maximum of the intense band (N→V) is the same for 1‐pentene, cis‐2‐pentene, and 2‐methyl‐2‐butene, with one, two, and three alkyl substituents, respectively. The results show that in a series of hydrocarbons, where the molecular weight is unchanged and the number of alkyl groups is the only variable, the position of the N→V maximum is not a function of the number of alkyl substituents. From the standpoint of methyl substituents, there is no shift between cis‐2‐pentene with one methyl group and 2‐methyl‐2‐butene with three. In the absence of such a shift, spectral evidence in support of hyperconjugation in the substituted ethylenes is lacking.The N→V maximum for trans‐2‐pentene is less intense and at somewhat longer wavelength than for the cis‐isomer. The greatest shift in this band is with 2‐methyl‐1‐butene, where the two alkyl groups are on the same carbon a...