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  • spectra
  • Fourier-transform spectroscopy is a measurement technique whereby spectra are collected based on measurements of the coherence of a radiative source, using time-domain or space-domain measurements of the electromagnetic radiation or other type of radiation. (wikipedia.org)
  • Accordingly, the technique of "Fourier-transform spectroscopy" can be used both for measuring emission spectra (for example, the emission spectrum of a star), and absorption spectra (for example, the absorption spectrum of a liquid). (wikipedia.org)
  • ENDOR spectra contain information on the type of nuclei in the vicinity of the unpaired electron (NZ and EZ), on the distances between nuclei and on the spin density distribution (HFS) and on the electric field gradient at the nuclei (Q). The right figure illustrates the energy diagram of the simplest spin system where a is the isotropic hyperfine coupling constant in hertz (Hz). (wikipedia.org)
  • ions
  • Early experiments used conventional electron impact ion sources but these sources were found to be unsuitable for producing ions to trap in an argon matrix due to the energy of the ions. (canterbury.ac.nz)
  • These magnetic properties point to a spin-coupled iron cluster, with a minimum of two iron ions. (biomedsearch.com)
  • The ions are described by their oxidation state and their ease of formation can be inferred from the ionization potential (for cations) or from the electron affinity (anions) of the parent elements. (wikipedia.org)
  • nucleus
  • For NMR spectroscopy, the corresponding resonance equation is h ν = g N μ N B 0 {\displaystyle h\nu =g_{\mathrm {N} }\mu _{\mathrm {N} }B_{0}} where g N {\displaystyle g_{\mathrm {N} }} and μ N {\displaystyle \mu _{\mathrm {N} }} depend on the nucleus under study. (wikipedia.org)
  • T 1 e {\displaystyle T_{\mathrm {1e} }} and T 1 n {\displaystyle T_{\mathrm {1n} }} are the spin-lattice relaxation time for the electron and the nucleus respectively. (wikipedia.org)
  • atom's
  • At even higher field strength, when the strength of the external field is comparable to the strength of the atom's internal field, electron coupling is disturbed and the spectral lines rearrange. (wikipedia.org)
  • Muonium is usually studied by muon spin rotation, in which the Mu atom's spin precesses in a magnetic field applied transverse to the muon spin direction (since muons are typically produced in a spin-polarized state from the decay of pions), and by avoided level crossing (ALC), which is also called level crossing resonance (LCR). (wikipedia.org)
  • magnetic field
  • The nitroxide spin-label 3-beta-doxyl-5-alpha-cholestane (cholestane) was incorporated into DMPC/DHPC bicelles to report the alignment of bicelles in the static magnetic field. (biomedsearch.com)
  • If the spin-orbit interaction dominates over the effect of the external magnetic field, L → {\displaystyle \scriptstyle {\vec {L}}} and S → {\displaystyle \scriptstyle {\vec {S}}} are not separately conserved, only the total angular momentum J → = L → + S → {\displaystyle \scriptstyle {\vec {J}}={\vec {L}}+{\vec {S}}} is. (wikipedia.org)
  • For the microwave frequency of 9388.2 MHz, the predicted resonance occurs at a magnetic field of about B 0 = h ν / g e μ B {\displaystyle B_{0}=h\nu /g_{e}\mu _{\text{B}}} = 0.3350 teslas = 3350 gausses. (wikipedia.org)
  • displaystyle
  • Therefore, the separation between the lower and the upper state is Δ E = g e μ B B 0 {\displaystyle \Delta E=g_{e}\mu _{\text{B}}B_{0}} for unpaired free electrons. (wikipedia.org)
  • An unpaired electron can move between the two energy levels by either absorbing or emitting a photon of energy h ν {\displaystyle h\nu } such that the resonance condition, h ν = Δ E {\displaystyle h\nu =\Delta E} , is obeyed. (wikipedia.org)
  • atom
  • The stability of this radical is attributed to the resonance provided by non-bonding electrons on the nitrogen atom, which form a 2c3e (half-) bond between nitrogen and oxygen as well as Hyperconjugation. (wikipedia.org)
  • spectrum
  • The term Fourier-transform spectroscopy reflects the fact that in all these techniques, a Fourier transform is required to turn the raw data into the actual spectrum, and in many of the cases in optics involving interferometers, is based on the Wiener-Khinchin theorem. (wikipedia.org)
  • One of the most basic tasks in spectroscopy is to characterize the spectrum of a light source: how much light is emitted at each different wavelength. (wikipedia.org)
  • pairs
  • Substituents that can donate electron pairs may stabilize the singlet state by delocalizing the pair into an empty p-orbital. (wikipedia.org)
  • probe
  • We used an ESR spectrometer and 16-doxyl stearic acid as spin probe to measure conformational changes in albumin in blood samples from a population of healthy donors and volunteers (n=349), patients with a wide variety of hematologic and nonhematologic malignancy (n=135), and patients with chronic diseases such as gastrointestinal and pulmonary disease, diabetes, and cirrhosis (n=91). (sigmaaldrich.com)
  • We added differing amounts of 16-doxyl stearic acid spin probe in ethanol to 50 microL of serum from each patient to create 3 different aliquots that differed in concentration of spin probe and ethanol, then incubated the aliquots for 10 min at 37 degrees C with continuous shaking. (sigmaaldrich.com)
  • methyl
  • Interdigitation causes a large increase in the order parameter of a fatty acid spin labeled near the terminal methyl, 16-doxylstearate, so that it was similar to that of a fatty acid labeled much closer to the polar head group region, 5-doxylstearate. (biomedsearch.com)
  • applications
  • This report focuses on the global market of spectroscopy products and provides an updated review, including its applications in various applications. (gii.co.jp)
  • total
  • Această detectare de cantități extrem de mici de spini electronici neîmperecheați, adică cu spin total differit de zero, face ca tehnica RES să fie extrem de utilă în studiul radicalilor liberi în chimie, ionilor paramagnetici în chimia fizică, diferitelor efecte biochimice și biofizice în medicină și fiziologie. (wikipedia.org)
  • The report deals with spectroscopy products covering the total market, which includes three main industries: pharmaceutical and biotechnology, food and beverage, and environmental industries. (gii.co.jp)
  • single
  • Radical reaction mechanisms use single-headed arrows to depict the movement of single electrons: The homolytic cleavage of the breaking bond is drawn with a 'fish-hook' arrow to distinguish from the usual movement of two electrons depicted by a standard curly arrow. (wikipedia.org)
  • pair
  • For example, if a substituent is able to donate a pair of electrons, most likely carbene will not be electrophilic. (wikipedia.org)
  • Raman
  • This phenomenon is important for applications such as near-field microscopy, biosensing, surface enhanced Raman spectroscopy and nano-antennae. (psi.ch)
  • Deep-ultraviolet surface-enhanced resonance Raman scattering of adenine on aluminum nanoparticle arrays, S. K. Jha, Z. Ahmed, M. Agio, Y. Ekinci, and J. F. Löffler, J. Am. Chem. (psi.ch)
  • In this context it is hardly surprising that the development of miniaturised Raman spectrometers with mass less than about 1kg is already far advanced and space mission trials are envis- aged for the adoption of Raman spectroscopy as a novel technology for molecular characterisation, either alone or in conjunction with laser ablation techniques, on future planned Mars robotic missions as part of lander and rover life-detection instrumentation . (binaryoptions-online.com)
  • The rotational spectra of non-polar molecules cannot be observed by those methods, but can be observed and measured by Raman spectroscopy. (wikipedia.org)
  • fluorescence
  • Optical design considerations and performance of a spectro streak apparatus for time resolved fluorescence spectroscopy. (mpg.de)
  • Physical characterization can be performed using a range of techniques including dynamic light scattering for nanoparticle size determination, transmission electron microscopy, optical fluorescence, gel electrophoresis, and iron and gadolinium concentration determination by inductively-coupled mass spectrometry. (birc.ca)
  • variety of measurement tools such as autocorrelators, SPIDER and cross-correlator and a femtosecond dynamic research tools such as Beacon fluorescence up-conversion and Hatteras transient spectroscopy pump-probe systems. (dmphotonics.com)
  • molecular
  • Today, researchers focus on specialized topics, such as the design and synthesis of molecular magnets or other model systems in order to understand and harness the fundamental principles behind phenomena such as the relation between magnetism and chemical reactivity as well as microstructure related mechanical properties of metals and the biochemical impact of spin (e. g. photoreceptor proteins) and spin transport. (wikipedia.org)
  • atom's
  • Muonium is usually studied by muon spin rotation, in which the Mu atom's spin precesses in a magnetic field applied transverse to the muon spin direction (since muons are typically produced in a spin-polarized state from the decay of pions), and by avoided level crossing (ALC), which is also called level crossing resonance (LCR). (wikipedia.org)
  • This function can be used to calculate the probability of finding any electron of an atom in any specific region around the atom's nucleus. (wikipedia.org)
  • When more electrons are added to a single atom, the additional electrons tend to more evenly fill in a volume of space around the nucleus so that the resulting collection (sometimes termed the atom's "electron cloud") tends toward a generally spherical zone of probability describing the electron's location, because of the uncertainty principle. (wikipedia.org)
  • Relaxation
  • HFB has a single narrow 19F NMR signal and the spin lattice relaxation rate is highly sensitive to changes in pO2, yet minimally responsive to temperature. (wikipedia.org)
  • proteins
  • SDSL has been established as a tool for investigating solution structure and dynamics of proteins, especially for those systems that are difficult to study by X-ray crystallography and NMR spectroscopy. (usc.edu)
  • Laboratory
  • In the laboratory hexafluorobenzene is used as standard in fluorine-19 NMR spectroscopy, solvent and standard in carbon-13 NMR, solvent in proton NMR, solvent when studying some parts in the Infrared and solvent in Ultraviolet-visible spectroscopy, as hexafluorobenzene itself hardly shows any absorbance in the UV region. (wikipedia.org)
  • Current projects in astrochemistry involve both laboratory microwave spectroscopy and observations made using modern radiotelescopes such as the Atacama Large Millimetre Array (ALMA). (wikipedia.org)
  • lattice
  • As a result, the effect of the lattice potential can be incorporated into the effective masses of the electron and hole. (wikipedia.org)
  • novel
  • In addition, spin engineering exploits the functionality of spin to design materials with novel properties as well as to provide a better understanding and advanced applications of conventional material systems. (wikipedia.org)
  • decay
  • The recombination of the electron and hole, i.e. the decay of the exciton, is limited by resonance stabilization due to the overlap of the electron and hole wave functions, resulting in an extended lifetime for the exciton. (wikipedia.org)
  • Metals
  • Thus, the engineering of ferromagnetic materials like mu-metals or Alnico at the beginning of the last century can be considered as early examples of spin engineering, although the concept of spin was not yet known at that time. (wikipedia.org)
  • For the heavier transition metals, lanthanides and actinides, spin-orbit coupling cannot be ignored. (wikipedia.org)
  • chemical
  • Because of the basic importance of quantum spin for physical and chemical processes, spin engineering is relevant for a wide range of scientific and technological applications. (wikipedia.org)
  • Diamagnetism is a universal property of chemical compounds, because all chemical compounds contain electron pairs. (wikipedia.org)
  • energy
  • It also is the smallest one, so taking up an electron releases one of the largest amounts of energy of all elements, it is the strongest oxidant, and it has the highest electronegativity. (wikipedia.org)
  • Consequently, the exciton has slightly less energy than the unbound electron and hole. (wikipedia.org)
  • Dynamic
  • Dynamic nuclear polarization (DNP) and spin exchange optical pumping (SEOP) facilities permit increases in signal of more than 10,000 times for 13 C and 129 Xe. (birc.ca)
  • Often
  • Often there is more than one band to choose from for the electron and the hole leading to different types of excitons in the same material. (wikipedia.org)
  • cannot
  • Thus, despite the popular analogy to planets revolving around the Sun, electrons cannot be described simply as solid particles. (wikipedia.org)
  • charge
  • The protons have a positive electric charge, the electrons have a negative electric charge, and the neutrons have no electric charge. (wikipedia.org)
  • If an atom has more or fewer electrons than protons, then it has an overall negative or positive charge, respectively, and it is called an ion. (wikipedia.org)
  • The charge on the electron acts like it is smeared out in space in a continuous distribution, proportional at any point to the squared magnitude of the electron's wave function. (wikipedia.org)
  • found
  • Spintronics is probably one of the most advanced fields of spin engineering with many important inventions which can be found in end-user devices like the reading heads for magnetic hard disk drives. (wikipedia.org)