Intramolecular charge-transfer absorption spectra of formamide and acrolein

Abstract

To test further Nagakura and Tanaka's conception of intramolecular charge-transfer absorption, an improved calculation based on LonguetHiggins and Murrell's method was carried out for the w-electron structures of formamide and acrolein. This shows that the 1717 ~, band of formamide and 1935 ~, band of acrolein can be regarded as intramolecuIar charge-transfer absorption bands in the sense that the excited state wave functions for these two bands are mainly constructed of the charge-transfer configuration, and that the transitions corresponding to these bands are accompanied by a large amount of electron transfer from electron donor towards acceptor. The 1717 A band of formamide can not be interpreted as a shifted 1560 ~, formaldehyde band. The latter band must shift to shorter wavelengths as the result of interaction with non-bonding electrons of the nitrogen atom. Similar blue shifts occur in acrolein for the C = C and C ---O zr -~Tr ~ bands relative to the corresponding bands of ethylene and formaldehyde. Similar causes operate in the blue shifts of the non-charge-transfer bands of donor-acceptor molecular complexes.

Chemical Reactivity of Trimethylsilyl Azide in Gas Phase Synthesis of Ultrafine Particles from Acrolein.

“…As is shown in Fig. 1, the n is * absorption band of AC molecule in the 300-400 nm region [10,11] decreased its intensity by ca. 70% in 90 min, showing that the carbonyl group in AC molecule interacted with TMSAZ.…”

Atmospheric photodissociation lifetimes for nitromethane, methyl nitrite, and methyl nitrate

“…The photoabsorption spectrum of gaseous CHsN02 has been previously investigated over the limited region from 205 to 335 nm [26], and these cross sections are in agreement with our results. Nagakura [27] studied the short-wavelength absorption band and found a maximum at this work; ( --1, from [27].…”

“…T * transition of a nonbonding electron on an oxygen atom, while the short-wavelength band is caused by a 7r -7r* transition [26,27,29]. Photoabsorption by CHBNO~ results chiefly in the primary process (12) CH3N02 + hv + CH3 + NO2 with smaller yields coming from the following reactions [10,25,28,30 (Fig.…”

Laser-Induced Polymeric Film and Particle Formation from a Gaseous Mixture of Methyl Acrylate and Acrolein

“…99, No. 19,1995 Morita and Shimizu 260-10 IR spectrophotometer and a Nicolet 740 FT-IR spectrometer. SEM micrographs were taken with a Topcon ABT-32 scanning electron microscope.…”