chlorophylls.mspct {photobiologyPlants}

Absorbance spectra for chlorophylls.

Description

Optical absorption spectra of chlorophyll a in methanol and chlorophylls a and by in diethyl ether containing the wavelengths at 1 nm interval.

Format

A filter_mspct with three member filter_spct objects each with variable number of rows and 2 numeric variables, w.length and A

Details

The variables of the member spectra are as follows:

• w.length (nm)

• A (spectral absorbance)

Data from PhotochemCAD 2.1a has been munged on 2 June 2017 by Scott Prahl (https://omlc.org/) to make the information available to non-Windows users. Although he has tried to be as careful as possible, he may have introduced some error; the cautious user is advised to compare these results with the original sources (Du et al., 1998; Dixon et al., 2005).

The spectral absorption measurements of chlorophyll a in methanol, chlorophyll a and chlorophyll b in diethyl ether were made by J. Li on 12-11-1997 using a Cary 3 spectrophotometer. The absorption values were collected using a spectral bandwidth of 1.0 nm, a signal averaging time of 0.133 sec, a data interval of 0.25 nm, and a scan rate of 112.5 nm/min.

Chlorophyll a measurements were scaled to make the molar extinction coefficient match the value of 111700 cm-1/M at 417.8 nm. These values were then interpolated to report extinction coefficients at regular 1 nm intervals. The reported molar extinction coefficient is from Strain et al. (1963).

Chlorophyll b measurements were scaled to make the molar extinction coefficient match the value of 159100 cm-1/M at 453.0 nm. These values were then interpolated to report extinction coefficients at regular 1 nm intervals. The reported molar extinction coefficient is from Vernon and Seely (1966).

Note

If you use these data in a publication, please cite also the original sources as given under references. For more information please visit https://omlc.org/.

References

J. M. Dixon, M. Taniguchi and J. S. Lindsey "PhotochemCAD 2. A refined program with accompanying spectral databases for photochemical calculations", Photochem. Photobiol., 81, 212-213, 2005.

H. Du, R. A. Fuh, J. Li, A. Corkan, J. S. Lindsey, "PhotochemCAD: A computer-aided design and research tool in photochemistry," Photochem. Photobiol., 68, 141-142, 1998.

Strain, H. H., M. R. Thomas and J. J. Katz (1963) Spectral absorption properties of ordinary and fully deuteriated chlorophylls a and b. Biochim. Biophys. Acta 75, 306-311.

Vernon, L. P. and G. R. Seely (1966) The chlorophylls. Academic Press, NY.

Examples

names(chlorophylls.mspct)
getWhatMeasured(chlorophylls.mspct[[1]])