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photobiologyPlants (version 0.4.3)

chlorophylls.mspct: 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.

Arguments

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. 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 1nm 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 1nm intervals. The reported molar extinction coefficient is from Vernon and Seely (1966).

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

Run this code
names(chlorophylls.mspct)
getWhatMeasured(chlorophylls.mspct[[1]])

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