(The image is taken from wikipedia https://en.wikipedia.org/wiki/Periodic_table_(crystal_structure) ,
and I claim no originality of creating the image)
The reason of the following structures are given in wikipedia, with some exceptions, at room temperature.
- usually BCC structure of alkali metal, group 5 (VB) and 6 (VIB) plus Mn and Fe
- usually FCC structure of Noble Gases (not helium), and near right end of transitional elements?
- usually HCP structure of group 3 (IIIB), 4 (IVB) and 12 (IIB) and also group 7(VIIB) and 8 (VIIIB, left group) except for first two (Fe, Mn)
- HCP and DHCP of lantahnides and actinides?
If all of these can be explained in terms of electronic configuration , then a significant electronic-to-crystal structure interrelation in simpler terms can be obtained.
(and possibly, ratio of metallic bandgap or Fermi energy etc. like energy parameters and average electron K.E at room temperature, then I think the correlation would be stronger. Perhaps, if one replaces spherical model of a metallic atom with its feasible 3D dirctional variation of outermost electron shell geometry, the the correlation is likely to be even stronger)
Ordered structures occur from the intrinsic nature of the constituent particles to form symmetric patterns ... Some directions and planes are defined by symmetry of the crystal system
Sorry, Hadi Jabbar Alagealy I have not understood what you have meant and how it would be related to my question.
The trends are well known, but it is difficult to say in a single sentence, why this trends exist. The following can, however, be stated:
-Mn, Fe, Co deviate from the trend because of the magnetic contribution to the thermodynamic functions.
-the total cohesive energy is much larger than the differences between the energies of the crystal structures. So there are non-obvious subtle effects which are responsible for the energy differences and which determine the observed crystal structures. Some quantitative thoughts can be found in
https://iopscience.iop.org/article/10.1088/0022-3719/3/2/018/meta
(quick find by google scholar)
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