What is the principle of electron paramagnetic resonance?
The basis of EPR spectroscopy lies in the spin of an electron and its associated magnetic moment. When an electron is placed within an applied magnetic field, Bo, the two possible spin states of the electron have different energies. This energy difference is a result of the Zeeman effect.
What is the principle of ESR?
PRINCIPLE: The Erythrocyte Sedimentation Rate (ESR) expresses in mm per hour the rate at which red blood cells settle when anti-coagulated blood is allowed to stand in a narrow tube (Westergren). It is measured by the height of the column of clear plasma at the end of one hour.
What is CW EPR?
Furthermore, X-band cw EPR allows for a quantification of the amount of NO-ligated globins, as was demonstrated Piknova et al. (2005), who developed an accurate assay to detect the level of nitrosyl hemoglobin in human blood.
What is G anisotropy?
This is the anisotropy of the electronic g-factor. An unpaired electron, in a molecule or radical, has its spin oriented by the magnetic field which it experiences. This field consists of the external field together with the field at the electron due to induced ring currents of the other electrons.
Why ESR is called EPR?
This absorption of microwave radiation takes place under the influence of an applied magnetic field. The substances with one or more unpaired electrons are paramagnetic and exhibit ESR. Thus, ESR spectroscopy is also called electron paramagnetic resonance (EPR) spectroscopy or electron magnetic resonance spectroscopy.
Where is EPR used?
EPR/ESR spectroscopy is used in various branches of science, such as biology, chemistry and physics, for the detection and identification of free radicals in the solid, liquid, or gaseous state, and in paramagnetic centers such as F-centers.
What are the principal methods used to determine the erythrocyte sedimentation rate?
There are two main methods used to measure the ESR: the Westergren method and the Wintrobe Method. Each method produces slightly different results.
What is Q band in EPR?
Enables Operation at Variable Sample Temperatures from 4 K to 300 K and Features an Optical Window. Investigations at Q-band (34 GHz) answer questions which can not be solved at lower microwave frequencies, like. the determination of g-factor variations of multi compounded substances.
What is hyperfine splitting in ESR spectroscopy?
The hyperfine splitting (hfs) is a special feature of ESR caused by the interaction of electron spins with the magnetic nuclei in the sample. A magnetic nucleus with quantum number I will split a single ESR line (peak) into 2I+1 lines (peaks).
What is g tensor?
The g tensor is a fundamental quantity of molecules and impurity centers in solids characterizing the magnitude and anisotropy of their magnetic moment in a given electronic state. Experimentally, this quantity is most often extracted from EPR spectroscopy [1,2].