enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Bond energy - Wikipedia

    en.wikipedia.org/wiki/Bond_energy

    In chemistry, bond energy (BE) is one measure of the strength of a chemical bond. It is sometimes called the mean bond , bond enthalpy , average bond enthalpy , or bond strength . [ 1 ] [ 2 ] [ 3 ] IUPAC defines bond energy as the average value of the gas-phase bond-dissociation energy (usually at a temperature of 298.15 K) for all bonds of the ...

  3. Bond-dissociation energy - Wikipedia

    en.wikipedia.org/wiki/Bond-dissociation_energy

    The term bond-dissociation energy is similar to the related notion of bond-dissociation enthalpy (or bond enthalpy), which is sometimes used interchangeably.However, some authors make the distinction that the bond-dissociation energy (D 0) refers to the enthalpy change at 0 K, while the term bond-dissociation enthalpy is used for the enthalpy change at 298 K (unambiguously denoted DH° 298).

  4. Binding energy - Wikipedia

    en.wikipedia.org/wiki/Binding_energy

    In physics and chemistry, binding energy is the smallest amount of energy required to remove a particle from a system of particles or to disassemble a system of particles into individual parts. [1] In the former meaning the term is predominantly used in condensed matter physics , atomic physics , and chemistry, whereas in nuclear physics the ...

  5. Standard enthalpy of reaction - Wikipedia

    en.wikipedia.org/wiki/Standard_enthalpy_of_reaction

    Such thermal energy manifests itself, however, in changes in the non-chemical state variables (such as temperature, pressure, volume) of the joint systems, as well as the changes in the mole numbers of the chemical constituents that describe the chemical reaction. [citation needed] Internal energy is defined with respect to some standard state.

  6. Walsh diagram - Wikipedia

    en.wikipedia.org/wiki/Walsh_diagram

    For the simplest AH 2 molecular system, Walsh produced the first angular correlation diagram by plotting the ab initio orbital energy curves for the canonical molecular orbitals while changing the bond angle from 90° to 180°. As the bond angle is distorted, the energy for each of the orbitals can be followed along the lines, allowing a quick ...

  7. Tight binding - Wikipedia

    en.wikipedia.org/wiki/Tight_binding

    The energy E i is the ionization energy corresponding to the chosen atomic orbital and U is the energy shift of the orbital as a result of the potential of neighboring atoms. The n ± 1 | H | n = − Δ {\displaystyle \langle n\pm 1|H|n\rangle =-\Delta } elements, which are the Slater and Koster interatomic matrix elements , are the bond ...

  8. Molecular mechanics - Wikipedia

    en.wikipedia.org/wiki/Molecular_mechanics

    A force field is used to minimize the bond stretching energy of this ethane molecule.. Molecular mechanics uses classical mechanics to model molecular systems. The Born–Oppenheimer approximation is assumed valid and the potential energy of all systems is calculated as a function of the nuclear coordinates using force fields.

  9. Ligand efficiency - Wikipedia

    en.wikipedia.org/wiki/Ligand_efficiency

    Ligand efficiency is a measurement of the binding energy per atom of a ligand to its binding partner, such as a receptor or enzyme. [1]Ligand efficiency is used in drug discovery research programs to assist in narrowing focus to lead compounds with optimal combinations of physicochemical properties and pharmacological properties.