Ultraviolet absorption cross sections and atmospheric photodissociation rate constants of formaldehyde

Journal Article · Thu May 17 04:00:00 EDT 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100373a025· OSTI ID:6374137

Rogers, J D ^[1]

---

1. General Motors Research Labs., Warren, MI (USA)

Ultraviolet absorption cross sections of gas-phase formaldehyde were measured over the wavelength range of 235-365 nm using a Bomem Fourier transform spectrometer. The uncertainties in the measured cross sections were 1-2%, including the estimated effect of systematic errors. The sum of the cross sections in the wavelength region between 300 and 365 nm was about 6% larger than the previous best estimate of this sum. These new UV cross sections were used to calculate photodissociation rate constants for formaldehyde for the {phi}{sub 1} photolysis channel (HCHO {yields} H + HCO) and the {phi}{sub 2} photolysis channel (HCHO {yields} H{sub 2} + CO) at solar zenith angles ranging from 0{degree} to 86{degree}. The new photodissociation rate constants were about 8% larger for the {phi}{sub 1} channel and about 10% smaller for the {phi}{sub 2} channel than the currently accepted values for these rate constants.

• OSTI ID: 6374137
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:10; ISSN JPCHA; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500 -- Photochemistry
54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
ALDEHYDES
ATMOSPHERIC CHEMISTRY
CHEMISTRY
CROSS SECTIONS
DATA
DATA ANALYSIS
ELECTROMAGNETIC RADIATION
EXPERIMENTAL DATA
FORMALDEHYDE
INFORMATION
KINETICS
MEASURING INSTRUMENTS
MEASURING METHODS
NUMERICAL DATA
ORGANIC COMPOUNDS
RADIATIONS
ULTRAVIOLET RADIATION