The frequency spectrum born from the electromagnetic radiation that is emitted as a result of the transition of a molecule or atom to a lower energy level explains what is defined as the emission spectrum.
Emission spectrum is an expression associated with chemical compounds or elements that is used in the scientific field to refer to the frequency spectrum that arises in terms of the emission of electromagnetic radiation when there are electronic transitions in a molecule or an atom that range from high levels of energy to lower states.
The difference in energy that arises from these two levels is equal to the photon energy that is emitted. It is interesting to note, at this point, that for each atom there are multiple possible electron transitions and each of these phenomena presents a difference in specific energy. This range of transitions leads to a wide variety of radiated wavelengths : hence, each emission spectrum arises.
Before continuing to share data of interest on this topic, it is worth noting that physics experts define emission as a particle process characterized by the conversion of a high-energy quantum mechanical state to a lower level when a photon is emitted. The resulting effect of this is the generation of light .
Characteristics of the emission spectrum
To appreciate the characteristics of emission spectra, it is essential to know and master several principles and concepts. It is necessary to know, specifically, what spectroscopy is about and what it consists of and, within that framework, to have information in relation to electromagnetic spectra , the nature of light , molecular and atomic emission mechanisms, etc. It is also necessary to learn about spectroscopic techniques and spectral line analysis.
With a solid information base, it is possible to interpret without major complications, for example, that the presence of certain colors within the atomic emission spectrum of a certain element accounts for the specific emission of certain frequencies of light . There is a formula based on the energy of the photon , the frequency and Planck's constant that allows us to deduce that an atom only emits photons with particular energies. This guideline of the atomic emission spectrum leads to understanding, specifically, how chromatic diversity arises in a neon sign .
As it is always different depending on the element of the periodic table analyzed, the emission spectrum is key to being able to stipulate how a certain material is composed.
If working with hydrogen , to point out a possibility, it may happen that the sample evaluated has more than one hydrogen atom with a different initial energy state and capable of reaching different final energy states. As a consequence of these multiple combinations, many emissions with different wavelengths come to light simultaneously.
Nor should we lose sight of the classification that leads to the distinction between continuous spectrum , band spectrum , line spectrum , absorption spectrum , visible spectrum , discontinuous spectrum and more.
In several planetary nebulae, the central stars show class O spectra and a percentage of them show hydrogen deficiency.
Emission spectroscopy
Emission spectroscopy is the name of a spectroscopic profiling technique that focuses on the wavelength of photons that, within the framework of the transition from an excited state to another with less energy, are emitted by molecules or atoms .
It is a procedure that was developed at the end of the 19th century . The scientific energy aimed at strengthening the theoretical explanation of the atomic emission spectrum led to what is known today as quantum mechanics .
By deepening the knowledge about this technique frequently mentioned as optical emission spectroscopy, categories such as flame emission spectroscopy come to light (which, broadly speaking, can be observed by using only a sample of metallic salts and a flame with the objective of performing the flame test ), fluorescence spectroscopy and absorption spectroscopy , among others.
It is even worth learning that the energy that appears in the form of light from compounds or elements heated by an electric arc or in a flame is analyzed using a spectroscope . This is the name of an instrument, also called a spectrometer , which leads to obtaining a discontinuous spectrum by allowing the separation of units that constitute light and are characterized by having different wavelengths .
Each of the elements in the periodic table has a different emission spectrum: that is why it is possible to determine how a material is composed.
Broadcast Spectrum Utilities
The emission spectrum can be used to establish the composition of a certain material. Through the technique known as astronomical spectroscopy , to indicate a case for reference, it is possible to analyze the light received and from these results identify how the stars are made.
An emission spectrum of molecules , in this context, is a valuable tool when carrying out a chemical analysis of a certain substance. Those who investigate organic compounds or carry out chemical, medical or molecular biology studies, for their part, find fluorescence spectroscopy extremely useful.
The method identified as atomic emission spectroscopy , to add another precision, enables examinations of biological, clinical and geological samples, among others.