Spectroscopy was originally the study of the interaction between radiation and matter as a function of wavelength (λ). In Optics, dispersion is the phenomenon in which the Phase velocity of a wave depends on its frequency A triangle is one of the basic Shapes of Geometry: a Polygon with three corners or vertices and three sides or edges which are Line Radiation, as in Physics, is Energy in the form of waves or moving Subatomic particles emitted by an atom or other body as it changes from a higher energy Matter is commonly defined as being anything that has mass and that takes up space. In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. In fact, historically, spectroscopy referred to the use of visible light dispersed according to its wavelength, e. g. by a prism. In Optics, a prism is a transparent optical element with flat polished surfaces that refract Light. Later the concept was expanded greatly to comprise any measurement of a quantity as function of either wavelength or frequency. Frequency is a measure of the number of occurrences of a repeating event per unit Time. Thus it also can refer to interactions with particle radiation or to a response to an alternating field or varying frequency (ν). Particle radiation is the radiation of Energy by means of fast-moving Subatomic particles. A further extension of the scope of the definition added energy (E) as a variable, once the very close relationship E=hν for photons was realized. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός The Planck constant (denoted h\ is a Physical constant used to describe the sizes of quanta. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena A plot of the response as a function of wavelength — or more commonly frequency — is referred to as a spectrum; see also spectral linewidth. A spectrum (plural spectra or spectrums) is a condition that is not limited to a specific set of values but can vary infinitely within a continuum. The spectral linewidth characterizes the width of a Spectral line, such as in the electromagnetic emission spectrum of an atom or the Frequency spectrum
Spectrometry refers to when a spectroscopic technique is used to assess the concentration or amount of a given species. In those cases, the instrument that performs such measurements is a spectrometer or spectrograph. A spectrometer is an Optical instrument used to measure properties of Light over a specific portion of the Electromagnetic spectrum, typically used
Spectroscopy/spectrometry is often used in physical and analytical chemistry for the identification of substances through the spectrum emitted from or absorbed by them. Physical chemistry, is the application of Physics to macroscopic microscopic atomic subatomic and particulate phenomena in chemical systems It is mostly defined as a large Analytical chemistry is the study of the Chemical composition of natural and artificial Materials.
Spectroscopy/spectrometry is also heavily used in astronomy and remote sensing. Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study Remote sensing is the small or large-scale acquisition of information of an object or phenomenon by the use of either recording or real-time sensing device(s that is not in physical Most large telescopes have spectrometers, which are used either to measure the chemical composition and physical properties of astronomical objects or to measure their velocities from the Doppler shift of their spectral lines. A telescope is an instrument designed for the observation of remote objects and the collection of Electromagnetic radiation. The Doppler effect (or Doppler shift) named after Christian Doppler, is the change in Frequency and Wavelength of a Wave for A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range compared
The type of spectroscopy depends on the physical quantity measured. The Sun (Sol is the Star at the center of the Solar System. In Physics and Optics, the Fraunhofer lines are a set of Spectral lines named for the German physicist Joseph von Fraunhofer ( 1787 Normally, the quantity that is measured is an intensity, either of energy absorbed or produced.
Most spectroscopic methods are differentiated as either atomic or molecular based on whether or not they apply to atoms or molecules. History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by Along with that distinction, they can be classified on the nature of their interaction:
Absorption spectroscopy is a technique in which the power of a beam of light measured before and after interaction with a sample is compared. Absorption spectroscopy refers to a range of techniques employing the interaction of electromagnetic radiation with matter When performed with tunable diode laser, it is often referred to as Tunable diode laser absorption spectroscopy (TDLAS). Tunable diode laser absorption spectroscopy ( TDLAS) is a technique for measuring the concentration of certain species such as Methane, Water vapor Tunable diode laser absorption spectroscopy ( TDLAS) is a technique for measuring the concentration of certain species such as Methane, Water vapor It is also often combined with a modulation technique, most often wavelength modulation spectrometry (WMS) and occasionally frequence modulation spectrometry (FMS) in order to reduce the noise in the system.
Fluorescence spectroscopy uses higher energy photons to excite a sample, which will then emit lower energy photons. A fluorescent lamp or fluorescent tube is a Gas-discharge lamp that uses Electricity to excite mercury Vapor. Mercury (ˈmɜrkjʊri also called quicksilver or hydrargyrum, is a Chemical element with the symbol Hg ( Latinized hydrargyrum Fluorescence spectroscopy aka fluorometry or spectrofluorometry is a type of Electromagnetic spectroscopy which analyzes Fluorescence from a sample In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena This technique has become popular for its biochemical and medical applications, and can be used for confocal microscopy, fluorescence resonance energy transfer, and fluorescence lifetime imaging. Biochemistry is the study of the chemical processes in living Organisms It deals with the Structure and function of cellular components such as Confocal microscopy is an optical imaging technique used to increase Micrograph contrast and/or to Reconstruct three-dimensional Images by Förster resonance energy transfer (abbreviated FRET) also known as Fluoresence resonance energy transfer or resonance energy transfer ( RET Fluorescence lifetime imaging or FLIM is a powerful tool for producing an image based on the differences in the exponential decay rate of the Fluorescence from a fluorescent
When X-rays of sufficient frequency (energy) interact with a substance, inner shell electrons in the atom are excited to outer empty orbitals, or they may be removed completely, ionizing the atom. X-ray spectroscopy is a gathering name for several spectroscopic techniques for determining the electronic structure of materials by using X-ray excitation X-ray crystallography is a method of determining the arrangement of Atoms within a Crystal, in which a beam of X-rays strikes a crystal and scatters The inner shell "hole" will then be filled by electrons from outer orbitals. The energy available in this de-excitation process is emitted as radiation (fluorescence) or will remove other less-bound electrons from the atom (Auger effect). The absorption or emission frequencies (energies) are characteristic of the specific atom. In addition, for a specific atom small frequency (energy) variations occur which are characteristic of the chemical bonding. With a suitable apparatus, these characteristic X-ray frequencies or Auger electron energies can be measured. X-ray absorption and emission spectroscopy is used in chemistry and material sciences to determine elemental composition and chemical bonding.
X-ray crystallography is a scattering process; crystalline materials scatter X-rays at well-defined angles. If the wavelength of the incident X-rays is known, this allows calculation of the distances between planes of atoms within the crystal. The intensities of the scattered X-rays give information about the atomic positions and allow the arrangement of the atoms within the crystal structure to be calculated.
Liquid solution samples are aspirated into a burner or nebulizer/burner combination, desolvated, atomized, and sometimes excited to a higher energy electronic state. The use of a flame during analysis requires fuel and oxidant, typically in the form of gases. Common fuel gases used are acetylene (ethyne) or hydrogen. Acetylene ( IUPAC name ethyne), C2H2 is a Hydrocarbon belonging to the group of Alkynes It is the simplest of all alkynes Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Common oxidant gases used are oxygen, air, or nitrous oxide. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Nitrous oxide, commonly known as " laughing gas," is a Chemical compound with the Chemical formula N 2 O. These methods are often capable of analyzing metallic element analytes in the part per million, billion, or possibly lower concentration ranges. "Parts-per" notation is used especially in Science and Engineering, to denote Ratios (relative proportions in measured quantities particularly In Chemistry, concentration is the measure of how much of a given substance there is mixed with another substance Light detectors are needed to detect light with the analysis information coming from the flame.
Plasma Emission Spectroscopy In some ways similar to flame atomic emission spectroscopy, it has largely replaced it.
A direct-current plasma (DCP) is created by an electrical discharge between two electrodes. A plasma support gas is necessary, and Ar is common. Samples can be deposited on one of the electrodes, or if conducting can make up one electrode.
Spark or arc (emission) spectroscopy - is used for the analysis of metallic elements in solid samples. Inductively coupled plasma atomic emission spectroscopy (ICP-AES also referred to as inductively coupled plasma optical emission spectrometry (ICP-OES is an analytical technique used Laser-induced breakdown spectroscopy (LIBS is a type of atomic emission Spectroscopy which utilises a highly energetic Laser pulse as the excitation source For non-conductive materials, a sample is ground with graphite powder to make it conductive. In traditional arc spectroscopy methods, a sample of the solid was commonly ground up and destroyed during analysis. An electric arc or spark is passed through the sample, heating the sample to a high temperature to excite the atoms in it. The excited analyte atoms glow emitting light at various wavelengths which could be detected by common spectroscopic methods. Since the conditions producing the arc emission typically are not controlled quantitatively, the analysis for the elements is qualitative. Nowadays, the spark sources with controlled discharges under an argon atmosphere allow that this method can be considered eminently quantitative, and its use is widely expanded worldwide through production control laboratories of foundries and steel mills.
Many atoms emit or absorb visible light. In order to obtain a fine line spectrum, the atoms must be in a gas phase. This means that the substance has to be vaporised. The spectrum is studied in absorption or emission. Visible absorption spectroscopy is often combined with UV absorption spectroscopy in UV/Vis spectroscopy. Ultraviolet-visible spectroscopy or ultraviolet-visible spectrophotometry ( UV/ VIS) involves the Spectroscopy of Photons in the UV-visible Although this form may be uncommon as the human eye is a similar indicator, it still proves useful when distinguishing colours.
All atoms absorb in the Ultraviolet (UV) region because these photons are energetic enough to excite outer electrons. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays If the frequency is high enough, photoionisation takes place. Photoionisation is the physical process in which an incident Photon ejects one or more Electrons from an Atom, Ion or Molecule UV spectroscopy is also used in quantifying protein and DNA concentration as well as the ratio of protein to DNA concentration in a solution. Several amino acids usually found in protein, such as tryptophan, absorb light in the 280nm range and DNA absorbs light in the 260nm range. For this reason, the ratio of 260/280nm absorbance is a good general indicator of the relative purity of a solution in terms of these two macromolecules. Reasonable estimates of protein or DNA concentration can also be made this way using Beer's law. In
Infrared spectroscopy offers the possibility to measure different types of inter atomic bond vibrations at different frequencies. Infrared spectroscopy (IR spectroscopy is the subset of Spectroscopy that deals with the Infrared region of the Electromagnetic spectrum. Especially in organic chemistry the analysis of IR absorption spectra shows what type of bonds are present in the sample. Organic chemistry is a discipline within Chemistry which involves the scientific study of the structure properties composition reactions, and preparation
Raman spectroscopy uses the inelastic scattering of light to analyse vibrational and rotational modes of molecules. Raman spectroscopy (pronounced S— is a spectroscopic technique used in Condensed matter physics and Chemistry to study vibrational rotational and The resulting 'fingerprints' are an aid to analysis.
Nuclear magnetic resonance spectroscopy analyzes the magnetic properties of certain atomic nuclei to determine different electronic local environments of hydrogen, carbon, or other atoms in an organic compound or other compound. Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy, is the name given to a technique which exploits the magnetic properties of certain nuclei Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. This is used to help determine the structure of the compound. Chemical structure refers to Molecular geometry, Electronic structure and Crystal structure.
Transmission or conversion-electron (CEMS) modes of Mössbauer spectroscopy probe the properties of specific isotope nuclei in different atomic environments by analyzing the resonant absorption of characteristic energy gamma-rays known as the Mössbauer effect. Mössbauer spectroscopy (Mößbauer is a spectroscopic technique based on the Mössbauer effect. The nucleus of an Atom is the very dense region consisting of Nucleons ( Protons and Neutrons, at the center of an atom Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions The Mössbauer effect (Mößbauer) a physical phenomenon discovered by Rudolf Mößbauer in 1957, refers to the resonant and recoil-free emission and absorption
Background subtraction is a term typically used in spectroscopy when one explains the process of acquiring a background radiation level (or ambient radiation level) and then makes an algorithmic adjustment to the data to obtain qualitative information about any deviations from the background, even when they are an order of magnitude less decipherable than the background itself.
Background subtraction can effect a number of statistical calculations (Continuum, Compton, Bremsstrahlung) leading to improved overall system performance.