Search results
Results From The WOW.Com Content Network
Furthermore, theories have been put forward to take into account the effects of vibronic coupling on electron transfer, in particular, the PKS theory of electron transfer. [10] In proteins, ET rates are governed by the bond structures: the electrons, in effect, tunnel through the bonds comprising the chain structure of the proteins. [11]
In theoretical chemistry, Marcus theory is a theory originally developed by Rudolph A. Marcus, starting in 1956, to explain the rates of electron transfer reactions – the rate at which an electron can move or jump from one chemical species (called the electron donor) to another (called the electron acceptor). [1]
The strongest bonds are formed by the sharing or transfer of electrons between atoms, allowing the formation of molecules. [17] Within a molecule, electrons move under the influence of several nuclei, and occupy molecular orbitals; much as they can occupy atomic orbitals in isolated atoms. [128]
Electrons in atoms and molecules can change (make transitions in) energy levels by emitting or absorbing a photon (of electromagnetic radiation), whose energy must be exactly equal to the energy difference between the two levels. Electrons can also be completely removed from a chemical species such as an atom, molecule, or ion.
Outer sphere electron transfer can occur between chemical species that are identical except for their oxidation state. [4] This process is termed self-exchange. An example is the degenerate reaction between the tetrahedral ions permanganate and manganate:
Heat transfer physics analyses may involve multiple scales (e.g., BTE using interaction rate from ab initio or classical MD) with states and kinetic related to thermal energy storage, transport and transformation. So, heat transfer physics covers the four principal energy carries and their kinetics from classical and quantum mechanical ...
Autotrophs can use this process to supply reducing power for inorganic carbon fixation. Reverse electron transfer ( RET ) is the process that can occur in respiring mitochondria , when a small fraction of electrons from reduced ubiquinol is driven upstream by the membrane potential towards mitochondrial complex I .
Electron capture is always an alternative decay mode for radioactive isotopes that do have sufficient energy to decay by positron emission. Electron capture is sometimes included as a type of beta decay , [ 1 ] because the basic nuclear process, mediated by the weak force, is the same.