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  2. Lattice energy - Wikipedia

    en.wikipedia.org/wiki/Lattice_energy

    Some chemistry textbooks [3] as well as the widely used CRC Handbook of Chemistry and Physics [4] define lattice energy with the opposite sign, i.e. as the energy required to convert the crystal into infinitely separated gaseous ions in vacuum, an endothermic process. Following this convention, the lattice energy of NaCl would be +786 kJ/mol.

  3. Crystal structure - Wikipedia

    en.wikipedia.org/wiki/Crystal_structure

    The hpc lattice (left) and the ccf lattice (right) The principles involved can be understood by considering the most efficient way of packing together equal-sized spheres and stacking close-packed atomic planes in three dimensions. For example, if plane A lies beneath plane B, there are two possible ways of placing an additional atom on top of ...

  4. Born–Landé equation - Wikipedia

    en.wikipedia.org/wiki/Born–Landé_equation

    The Born–Landé equation is a means of calculating the lattice energy of a crystalline ionic compound.In 1918 [1] Max Born and Alfred Landé proposed that the lattice energy could be derived from the electrostatic potential of the ionic lattice and a repulsive potential energy term.

  5. Born–Haber cycle - Wikipedia

    en.wikipedia.org/wiki/Born–Haber_cycle

    Born–Haber cycles are used primarily as a means of calculating lattice energy (or more precisely enthalpy [note 1]), which cannot otherwise be measured directly. The lattice enthalpy is the enthalpy change involved in the formation of an ionic compound from gaseous ions (an exothermic process ), or sometimes defined as the energy to break the ...

  6. Crystal system - Wikipedia

    en.wikipedia.org/wiki/Crystal_system

    A crystal system is a set of point groups in which the point groups themselves and their corresponding space groups are assigned to a lattice system. Of the 32 crystallographic point groups that exist in three dimensions, most are assigned to only one lattice system, in which case both the crystal and lattice systems have the same name. However ...

  7. Salt (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Salt_(chemistry)

    In chemistry, a salt or ionic ... The lattice energy is the summation of the interaction of all sites with all other sites. For unpolarizable spherical ions, only the ...

  8. Lattice constant - Wikipedia

    en.wikipedia.org/wiki/Lattice_constant

    Unit cell definition using parallelepiped with lengths a, b, c and angles between the sides given by α, β, γ [1]. A lattice constant or lattice parameter is one of the physical dimensions and angles that determine the geometry of the unit cells in a crystal lattice, and is proportional to the distance between atoms in the crystal.

  9. Terrace ledge kink model - Wikipedia

    en.wikipedia.org/wiki/Terrace_ledge_kink_model

    In chemistry, the terrace ledge kink (TLK) model, which is also referred to as the terrace step kink (TSK) model, describes the thermodynamics of crystal surface formation and transformation, as well as the energetics of surface defect formation. It is based upon the idea that the energy of an atom’s position on a crystal surface is ...