Structure determination of Pb13Mn9O25

Pb13Mn9O25, a complex oxide

solved from transmission

electron microscopy data

Ultramicroscopy 110

(2010) 881–890

Problem to solveNew unknown

compound in multiple

phased sampleAll phases

perovskite based

Peaks overlap in X-

ray data, so no

solution from that

So we turn to the

transmission electron

microscope...

Electron diffraction

gives us the cell

parameters and

space group.

a=b=14.2 Å=ap√13c=3.9 Å=ap

P4/m

EELS and EDX

give us the

composition.

Pb13Mn9O5

We collect the

intensities of the

reflections from

precession

electron

diffraction data.

We feed the

intensities and all

collected data to

direct methods

(SIR2008)

Pb

Mn

Perovskite subcell

Out comes a

solution for the

cation

positions.

Mn-vacancy

Pb

Mn

Perovskite subcell

There are

ordered

manganese

vacancies.

Mn-vacancy

But where is

the oxygen?

HAADF-STEM

confirms that Mn is

missing, but gives

no info on oxygen

We find the oxygen with

a global optimization in

direct space (FOX) using

the output from direct

methods as input.

Structure is solved with ...

two solutions !?

E = -7.42 eV E = -11.1 eV

Structure optimisation

favors one model

The calculated images

for this model agree well

with the experimental

HREM images

Joke Hadermann, Artem M. Abakumov, Alexander

A. Tsirlin, Mauro Gemmi, Hans D’Hondt, Vladimir

P.Filonenko, Julie Gonnissen, Haiyan Tan, Johan

Verbeeck, HelgeRosner, EvgenyV.Antipov

All precise details and data can be found in the

publication

Ultramicroscopy 110 (2010) 881–890

by the authors

Direct space structure solution from

precession electron diffraction data:

Resolving heavy and light

scatterers in Pb13Mn9O25