Spectral Line

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spectral line

[′spek·trəl ‚līn]
A discrete value of a quantity, such as frequency, wavelength, energy, or mass, whose spectrum is being investigated; one may observe a finite spread of values resulting from such factors as level width, Doppler broadening, and instrument imperfections. Also known as spectrum line.

Spectral Line


a thin line in an optical spectrum. Each such line can be characterized by a certain wavelength λ or frequency v = c/λ, where c is the speed of light. Spectral lines are observed in emission spectra as bright (colored) lines on a dark background and in absorption spectra as dark lines on a bright background. Each spectral line corresponds to a definite quantum transition in an atom, molecule, or crystal. Spectral lines are not strictly monochromatic: each one has a certain width Δλ.

References in periodicals archive ?
The small relative area as well as isomer shift ([delta] = 0.37 mm/s) and quadrupole splitting ([DELTA]EQ= - 0.45 mm/s) make difficult an assignment to a specific oxide or oxyhydroxide.
The calibration of the velocity scale was performed with [alpha]-Fe, and the isomer shifts are given with respect to the RT Mossbauer spectrum of [alpha]-Fe.
The separation of the ferrous and the ferric phases is based on values of two parameters such as isomer shifts (IS) and quadrupole splitting (QS).
Table 1: The parameters of quadrupole splitting ([DELTA][E.sub.Q]), isomer shifts ([delta]), and absorption area for ferrous gluconate and ferrous fumarate.
The determined values for the isomer shift [delta] and the quadrupole shift e are consistent with those reported for superparamagnetic particles of [Fe.sub.2][O.sub.3] [20,21].
The maghemite spectrum was modelled as a superposition of contributions from [sup.57]Fe nuclei in the tetrahedral (A) and octahedral (B) sites of spinel structure (with 3: 5 intensity ratio and 0.14 mm/s difference of isomer shifts [7]).
All the isomer shifts are given relative to the center of the a-Fe spectrum.