Cov txheej txheem:

Dab tsi yog cov ntsiab lus ntawm crystal symmetry?
Dab tsi yog cov ntsiab lus ntawm crystal symmetry?

Video: Dab tsi yog cov ntsiab lus ntawm crystal symmetry?

Video: Dab tsi yog cov ntsiab lus ntawm crystal symmetry?
Video: lub hom phiaj loj tshaj plaws ntawm kev ntseeg yog dab tsi 2024, Kaum ib hlis
Anonim

Yog li, lub Crystal no muaj cov hauv qab no symmetry:

  • 1 - 4-fold tig axis (A4)
  • 4 - 2-fold tig axes (A2), 2 txiav lub ntsej muag & 2 txiav cov npoo.
  • 5 daim iav dav hlau (m), 2 txiav hla lub ntsej muag, 2 txiav los ntawm cov npoo, thiab ib qho txiav kab rov tav los ntawm qhov chaw.

Ib yam li ntawd, dab tsi yog symmetry ntawm crystal?

siv lead ua symmetry Nyob rau hauv zoo-tsim siv lead ua , lub ntsej muag symmetrically teeb pom kev zoo sab hauv ntawm atoms. Lub dav hlau ntawm symmetry (tseem hu ua 'daim iav dav hlau' lossis ' symmetry plane') yog lub dav hlau uas tus siv lead ua yuav muab faib ua ob halves uas yog daim iav duab ntawm ib leeg.

Tom qab, lo lus nug yog, dab tsi yog qhov feem ntau symmetrical crystal system? triclinic, monoclinic, tetragonal hais txog ib qho ntawm xya siv lead ua systems . Cov feem ntau symmetrical ib yog kub qhov system thiab qhov tsawg kawg nkaus symmetrical yog triclinic.

Yog li ntawd, yuav ua li cas koj nrhiav tau lub symmetry ntawm ib lub caij?

Cov ntsiab lus symmetry uas lub molecule yuav muaj yog:

  1. E - tus kheej. Kev ua haujlwm ntawm tus kheej muaj kev ua tsis muaj dab tsi, thiab cov ntsiab lus sib luag yog tag nrho cov molecule.
  2. Cn - n-fold axis ntawm kev sib hloov. Kev sib hloov los ntawm 360 ° / n tawm ntawm cov molecule tsis hloov.
  3. σ - lub dav hlau ntawm symmetry.
  4. i - qhov chaw ntawm symmetry.

Dab tsi yog txhais los ntawm cov ntsiab lus symmetry?

A symmetry keeb yog ib txoj kab, dav hlau los yog taw tes rau hauv lossis los ntawm ib qho khoom, hais txog qhov kev sib hloov lossis kev xav tawm ntawm qhov khoom nyob rau hauv ib qho kev taw qhia indistinguishable ntawm tus thawj.

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