No. 14 P 1 21/c 1

Number

14

Hermann–Mauguin symbol

P 1 21/c 1

Hall symbol

-P 2ybc

Crystal system

Monoclinic

Operations per cell

4

General position

4e (site symmetry 1)

Wyckoff positions (standard setting)

How to read it

• Each symmetry element drawn in the cell is worked out from the group’s operations: rotation and screw axes as lines (arrow = direction; dashed = screw), mirror and glide planes as sheets (dashed outline = glide), inversion centres as dots; rotoinversion axes are dotted. Colours: 2-fold red, 3-fold green, 4-fold blue, 6-fold purple.
• The multiplicity is how many equivalent points an atom on that site generates in the conventional cell; the general position has the highest multiplicity, equal to the number of operations.
• Site symmetry is the point group that leaves that position fixed; a special position (lower multiplicity) sits on a symmetry element — press + on a row to see its atoms land on the drawn elements.

Crystal Lab structures in this group

• ZSM-5 (silicalite framework) (SiO₂ (MFI)) — Zeolite framework
• Sodium hexahydridoaluminate (Na₃AlH₆) — Complex hydride (cryolite-type)

Prototype structures in this group (98)

Cs₁₁O₃H₁₁Ir₂Mg₆Cr₂O₁₁Te₄Fe₂O₁₂S₃As₂Rh₂SrC₂Cu₃H₂O₈ G74Cl₂Hg₃O₂As₂S₃ D5fBi₂O₃Ca₂O₄SiCu₂O₄SeCl₂O₅Sb₄Ca₂O₅UGd₂O₅SiEr₂O₇Si₂Ca₂O₇P₂Na₂O₇U₂Al₂H₉O₁₁NP₂C₂CuNa₂O₆Bi₂MoO₆O₂Zr C43Ag₂SAs₂NdP₂ZnCl₂PdC₃₀H₃₀N₈O₈ZnO₃Pb₂Ag₃S₃SbCo₃Nd₄O₁₀Al₃C₄HNO₁₃P₃S₃Tl₄Mn₃O₆TeC₃H₆OO₃TeTl₂K₃SnTe₃Cl₃CuKO₃WC₄K₂N₄NiBa₄Ir₃O₁₀Cl₄(H₂O)IK H010O₇Si₂Y₂Cu₅O₁₀V₂Pt₅Se₄Cl₆K₂SnC₆H₄K₂N₆O₂PtS₆Ce₇Ge₂Pd₄F₇K₂Nb K62C₇H₅N₃O₆C₇H₈H₈K₂MnO₁₂S₂Al₉Co₂AgC₁₀H₄N₄CuH₂₀N₂O₁₄S H44OS₂Y₂AgTe₂Tl₃FeLi₂O₄SiClCsCu₅O₁₀V₂CuNa₂O₇P₂LiO₂SmAsS₂TlCaO₃Si S33(II)B₂H₆B₂H₆ClF₃CrTe₃CH₄N₂O₂AuBr₄(H₂O)₂K H419AuBr₄KCuO₄Te(NH₄)O₄S K41LaO₄PCdP₄MnO₆Sr₂TeAlF₆Na₃ J26PPd₆KNO₂MnHO₂ E06ErLiO₂BHO₂HgMnO₃AgCuO₄PAgMnO₄ H09GaPS₄CdCuO₆Se₂CHNaO₃ G012ClCuHOAsFeS E07ClIAsLiC₆Cl₆AsSAsS BlGeNaNSSe AlSeSe AkS