Electronically driven structural transitions in A10(PO4)6F2 apatites (A = Ca, Sr, Pb, Cd and Hg)

Balachandran, P.V.; Rajan, K.; Rondinelli, J.M.

doi:10.1107/S2052520614003710

Electronically driven structural transitions in A₁₀(PO₄)₆F₂ apatites (A = Ca, Sr, Pb, Cd and Hg)

P. V. Balachandran, K. Rajan and J. M. Rondinelli

It is shown that there is a dynamic lattice instability in the aristotype P6₃/m structure of A₁₀(PO₄)₆F₂ apatites containing divalent A-site Cd or Hg cations with (n - 1)d¹⁰ns⁰ electronic configurations. The distortion to a low-symmetry $P\bar{1}$ triclinic structure is driven by an electronic mechanism rather than from ionic size mismatch. Our theoretical work provides key insights into the role of the electronic configurations of A cations in fluorapatites.

Keywords: structural transitions; apatites; dynamic lattice instability.

Read article Similar articles

Supporting information

	Portable Document Format (PDF) file https://doi.org/10.1107/S2052520614003710/ps5032sup1.pdf Table of electronic configurations of pseudopotentials used and figure showing the low-energy zone-center phonons for Zn10(PO4)6F2
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup2.txt CIF file for Ca10(PO4)6F2 apatite in its ground state P63/m hexagonal symmetry from DFT
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup3.txt CIF file for Cd10(PO4)6F2 apatite in its aristotype P63/m hexagonal symmetry from DFT
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup4.txt CIF file for Cd10(PO4)6F2 apatite in its ground state P1 triclinic symmetry from DFT
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup5.txt CIF file for Hg10(PO4)6F2 apatite in its aristotype P63/m hexagonal symmetry from DFT
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup6.txt CIF file for Hg10(PO4)6F2 apatite in its ground state P1 triclinic symmetry from DFT
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup7.txt CIF file for Sr10(PO4)6F2 apatite in its ground state P63/mhexagonal symmetry from DFT
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup8.txt CIF file for Zn10(PO4)6F2 apatite in its ground state P63/m hexagonal symmetry from DFT
	Text file https://doi.org/10.1107/S2052520614003710/ps5032sup9.txt CIF file for Pb10(PO4)6F2 apatite in its ground state P63/m hexagonal symmetry from DFT

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Text
		Plain Text

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Text
		Plain Text

Search IUCr Journals		doi		Advanced search
Author		volume	page