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  2. Dibromomethane - Wikipedia

    en.wikipedia.org/wiki/Dibromomethane

    Dibromomethane is prepared commercially from dichloromethane via bromochloromethane: . 6 CH 2 Cl 2 + 3 Br 2 + 2 Al → 6 CH 2 BrCl + 2 AlCl 3 CH 2 Cl 2 + HBr → CH 2 BrCl + HCl. The latter route requires aluminium trichloride as a catalyst. [3]

  3. Chemical polarity - Wikipedia

    en.wikipedia.org/wiki/Chemical_polarity

    Note that the dipole moments drawn in this diagram represent the shift of the valence electrons as the origin of the charge, which is opposite the direction of the actual electric dipole moment. The bond dipole moment [5] uses the idea of electric dipole moment to measure the polarity of a chemical bond within a molecule. It occurs whenever ...

  4. Carbon tetrabromide - Wikipedia

    en.wikipedia.org/wiki/Carbon_tetrabromide

    Due to its symmetrically substituted tetrahedral structure, its dipole moment is 0 Debye. Critical temperature is 439 °C (712 K) and critical pressure is 4.26 MPa. [5]

  5. Electric dipole moment - Wikipedia

    en.wikipedia.org/wiki/Electric_dipole_moment

    The electric dipole moment is a measure of the separation of positive and negative electrical charges within a system: that is, a measure of the system's overall polarity. The SI unit for electric dipole moment is the coulomb-metre (C⋅m). The debye (D) is another unit of measurement used in atomic physics and chemistry.

  6. Polarizability - Wikipedia

    en.wikipedia.org/wiki/Polarizability

    The polarizability of an atom or molecule is defined as the ratio of its induced dipole moment to the local electric field; in a crystalline solid, one considers the dipole moment per unit cell. [1] Note that the local electric field seen by a molecule is generally different from the macroscopic electric field that would be measured externally.

  7. Dipole - Wikipedia

    en.wikipedia.org/wiki/Dipole

    The bent molecule H 2 O has a net dipole. The two bond dipoles do not cancel. The overall dipole moment of a molecule may be approximated as a vector sum of bond dipole moments. As a vector sum it depends on the relative orientation of the bonds, so that from the dipole moment information can be deduced about the molecular geometry.

  8. Polarization density - Wikipedia

    en.wikipedia.org/wiki/Polarization_density

    The net charge appearing as a result of polarization is called bound charge and denoted . This definition of polarization density as a "dipole moment per unit volume" is widely adopted, though in some cases it can lead to ambiguities and paradoxes. [5]

  9. Periodic boundary conditions - Wikipedia

    en.wikipedia.org/wiki/Periodic_boundary_conditions

    Maintenance of the minimum-image convention also generally requires that a spherical cutoff radius for nonbonded forces be at most half the length of one side of a cubic box. Even in electrostatically neutral systems, a net dipole moment of the unit cell can introduce a spurious bulk-surface energy, equivalent to pyroelectricity in polar ...