Application of Neutron Powder Diffraction in...

Application of Neutron Powder

Diffraction in Materials Science

NSRRC18, Taiwen Aug. 30, 2012

Qingzhen Huang

Qing.huang@nist.gov

NIST Center for Neutron Research, NIST, Gaithersburg, MD 20899

www.ncnr.nist.gov

KxFe2-ySe2

• Chemical composition, x & Y; • Symmetry of crystal structures; • Atoms distribution: Fe vacancy order • Magnetic ordering; • Symmetry of the magnetic structure; • Ordered magnetic moments;

• Relation with superconductivity.

Crystal and magnetic

Structures

Properties

1. Chemical composition 2. Atom and spin arrangements

We want to know: RELATIONSHIPS BETWEEN PROPERTIES AND STRUCTURES

Applications of powder diffraction in superconductivity

Position: 2dsinq = nl, where l is the incident beam wavelength, d and q are the distance between successive hkl planes and Bragg angles of reflections, respectively. Intensity: I = C|Fhkl|

2, where Fhkl is the amplitude of the diffracted X-ray or neutron hkl reflection. X-ray: Fhkl = ∑ fj exp(2pi (hx + ky + lz)) e-2W, where fj is the X-ray atomic scattering factor of atom j for X-ray. Neutron: Fhkl = ∑ bj exp(2pi (hx + ky + lz)) e-2W, where bj is the neutron scattering length for atom j. Magnetic: Fhkl = ∑ qj fMj exp(2pi (hx + ky + lz)) e-2W, where qj and fMj are the magnetic interaction vector and the magnetic form factor for atom j, respectively.

Neutron and X-ray powder diffraction

-1

0

1

2

3

4

5

6

7

-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 0.2 0.4 0.6 0.8 1

f (C

)

f (Co

3+)

sin

b(C)=0.6648 cm-12

-Neutron scattering length for Carbon

f(C)-Atomic scattering factor for Carbon

f(Co3+

)-Magnetic form factor for Cobalt

q ?l

Comparison of f(A), b(N), and f(M)

-0.5

0

0.5

1.0

1.5

0 10 20 30 40 50 60 70 80

Ne

utr

on S

catt

erin

g A

mplit

ude

s b

(cm

-12)

Atomic Number Z

H

He

Li

Be

B

C

N

OF

V

Mn

Cr

Fe

Co

Ni

Cu

Zn

Y

D Sr

Ba

Nd

Neutron Scattering Amplitudes

Definition of the vectors relevant in the evaluation of the magnetic structure factor.

e and k are unit vectors in the directions of the scattering and magnetic moment,

respectively. The magnetic interaction vector q is always perpendicular to the

scattering vector.

Information required Recommended

Phase identification & transition

Crystal structure determination & refinement

Light elements detection (H, Be, Li, B, C, N, O, F)

Symmetry analysis due to lattice distortion

Symmetry analysis due to light element shifting

Chemical order-disorder

Composition dependent analysis

Magnetic structure analysis & properties

P, I

P + I

I

P

I

P, I

I, P

P

XRD

XRD+NPD

NPD

XRD

NPD

XRD+NPD

XRD/NPD

NPD

Comparison of XRD and NPD techniques. P: position;

I: intensity of reflections. Intensity and resolution are

high for XRD and low for NPD.

NCNR High Resolution Neutron Powder Diffractometer

BT1

BT1

* Temperature: 0.3 - 1800 K;

* Magnetic Field: 0 - 9 T Vertical;

* More information at www.ncnr.nist.gov

Cu311 1.5401Å

Ge311 2.0784 Å

Ge733 1.1968Å

32 counters

Sample position

* 0 2q 165°

* Pressure: 0 – 1GPa;

Monochromator in-pile Collimation (arcmin)

Monochr. 2Theta

Relative Bragg Intensities

Flux (n s-1cm-2)

Wavelength (Å)

Relative # of reflections

Ge(311)

60'

75o

5.78

1,160,000

2.079

50

Ge(311) 15' 75o 2.86 570,000 2.079 50

Ge(311) 7' 75o 1.44 290,000 2.079 50

Cu(311)

60'

90o

1.84

870,000

1.540

100

Cu(311) 15' 90o 1.00 440,000 1.540 100

Cu(311) 7' 90o 0.54 230,000 1.540 100

Ge(733)

60'

120o

0.31

330,000

1.197

200

Ge(733) 15' 120o 0.20 200,000 1.197 200

Ge(733) 7' 120o 0.11 120,000 1.197 200

Parameters of monochromators

www.ncnr.nist.gov

BT1 Resolution of FWHM (degrees) as a function of 2q (degrees)

www.ncnr.nist.gov

Macromolecules

Zeolites

Minerals and Mining

Inorganic structures

Glass ceramics

Ceramic materials (incl medicals)

Metals and alloys

Cement

Polymers and Fibres

Pharmaceuticals

Forensic science

Materials for energy storage and conversion

Magnetic materials

Catalysis

Peroleum and Petrochemicals

Superconductivity

Composites

Paint and Pigments

Piezo ceramics

Aeronautics and Space Materials

Application of powder diffraction for:

PHYSICS 180 67.164 %

CHEMISTRY 72 26.866 %

MATERIALS SCIENCE 40 14.925 % METALLURGY METALLURGICAL ENGINEERING 15 5.597 %

SCIENCE TECHNOLOGY OTHER TOPICS 8 2.985 % ENGINEERING 5 1.866 %

CRYSTALLOGRAPHY 4 1.493 % ENVIRONMENTAL SCIENCES ECOLOGY 2 0.746 %

INSTRUMENTS INSTRUMENTATION 1 0.373 % MECHANICS 1 0.373 %

NUCLEAR SCIENCE TECHNOLOGY 1 0.373 % SPECTROSCOPY 1 0.373 %

学科 数目 %

2011-7-20

PHYSICAL REVIEW B 3.475 84 27.4510 %

JOURNAL OF SOLID STATE CHEMISTRY 2.34 41 13.3987 %

PHYSICAL REVIEW LETTERS 7.328 24 7.8431 %

PHYSICAL REVIEW B (CONDENSED MATTER AND MATERIALS PHYSICS) 3.475 19 6.2092 %

PHYSICA C 0.723 16 5.2288 %

JOURNAL OF ALLOYS AND COMPOUNDS 2.135 12 3.9216 %

JOURNAL OF APPLIED PHYSICS 2.072 11 3.5948 %

JOURNAL OF PHYSICS-CONDENSED MATTER 1.964 8 2.6144 %

JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS 1.118 5 1.6340 %

NATURE MATERIALS 29.504 5 1.6340 %

PHYSICA B-CONDENSED MATTER 1.056 5 1.6340 %

POWDER DIFFRACTION 0.512 5 1.6340 %

CHEMISTRY OF MATERIALS 5.368 4 1.3072 %

NATURE 34.48 4 1.3072 %

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS 0.723 4 1.3072 %

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 1.204 3 0.9804 %

JOURNAL OF PHYSICS: CONDENSED MATTER 1.964 3 0.9804 %

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 8.58 3 0.9804 %

PHYSICA B 1.056 2 0.6536 %

PROCEEDINGS 8TH INTERNATIONAL VACUUM ELECTRON SOURCES CONFERENCE AND NANOCARBON (2010) 2 0.6536 %

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 9.433 2 0.6536 %

SCIENCE 29.747 2 0.6536 %

SOLID STATE COMMUNICATIONS 1.873 2 0.6536 %

ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 1 0.3268 %

ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS 0.782 1 0.3268 %

合作发表研究论文的刊物

学术刊物 影响指数 篇数 %

2011-7-20

找到的结果数: ~282

被引频次总计[?] : ~9800

去除自引的被引频次总计: ~9500

施引文献[?] : ~6500

每项平均引用次数[?] : ~34

h-index [?] : ~51

引文报告 2012-7-1 作者=(huang q*) AND 地址=(gaithersburg) 入库时间=所有年份. 数据库=SCI-EXPANDED, CPCI-S.

合作发表研究论文概况

Relationships between carbon constant and property

in MgCxNi3 superconductor

Crystal Structure of Non-oxide

Perovskite Superconductor MgCxNi3. Pm3m, a Å

* Questions:

* C Structure Tc?

* C Tc ? T. He, Q. Huang, A. P. Ramirez, Y. Wang, K. A. Regan, N. Rogado, M. A. Hayward, M. K. Haas, J. S. Slusky, K. Inumaru, H. W. Zandbargen, N. P. Ong, and R. J. Cava. Superconductivity in the non-oxide Perovskite MgCNi3. Nature 411, 6833 (2001).

Carbon Content Affect Tc.

Tc Decreases Linearly with x Decreasing

0.5

0.6

0.8

1.0

1.1

0.84 0.88 0.92 0.96 1.0

U *

10

0

Carbon Content, x

(Å2)

U22

(Ni)

U11

(Ni)

Uiso

(Mg)

Variation of the Temperature Factors

as a Function of Carbon Content x for MgCxNi3

Carbon vacancy affects the position of the Ni atoms;

1000

1100

1200

1300

1400

1500

25 30 35 40 45 50

Co

unts

2 theta (deg)

(100) graphite

MgCxNi3, x

Neutron=0.968 (x

nom=1.05)

Short Range Crystallized Graphite

MgCxNi3, xNeutron=0.968, xNom=1.05

* Perovskite phase stability range

0.88 < x < 1.0 for MgCxNi3;

* Tc decreases systematically with

decreasing x;

* Carbon vacancy affects the position

of the Ni atoms;

What we have concluded:

Reveal the fundamental physics

in Fe-based superconductors

Structural and magnetic phase diagram of

CeFeAsO1-xFx and its relation to

high-temperature superconductivity

JUN ZHAO, Q. HUANG, CLARINA DE LA CRUZ, SHILIANG LI, J. W. LYNN, Y.

CHEN,M. A. GREEN, G. F. CHEN, G. LI, Z. LI, J. L. LUO, N. L. WANG AND

PENGCHENG DAI

NATURE MATERIALS, Vol. 7, 953 (2008)

Fe-based superconductivity

CeFeAsO1-xFx Struct. & Mag. as a Function of Temperature

Magnetic order close to superconductivity in the iron-based layered

LaO1-xFxFeAs systems

de la Cruz, C., Huang, Q., Lynn, JW , Li, JY ., Ratcliff, W .,

Zarestky, JL ., Mook, HA ., Chen, GF ., Luo, JL ., Wang, NL ., Dai, PC

NATURE, 453 (7197): 899-902 (2008)

Charge transform and magnetic order in Fe-based superconductors

RE3+O2-Fe2+As3-

Ba2+Fe2+2As3-

2 (1111)

(122)

CeO1-xFxFeAs

Magnetic controlled physical properties

1. Adjustable Zero Thermal Expansion in Antiperovskite

Manganese Nitride;

2. Magnetocaloric Materials for Commercial Refrigeration.

Adjustable Zero Thermal Expansion in Antiperovskite Manganese Nitride Xiaoyan Song, Zhonghua Sun, Qingzhen Huang, Markus Rettenmayr,

Xuemei Liu, Martin Seyring, Guannan Li, Guanghui Rao, and Fuxing Yin

Negative thermal expansion

Mn3-xCu0.5Ge0.5N Mag. & struct. vs temperature

Adv. Mater. (2011)

* Space telescopes

* Thermo-mechanical actuators

* Precision mechanics and

positioning devices

* Bragg grating wavelength filters

* Microelectronic components

Thermal expansion in materials

Low thermal expansion: |a| ≤ 2.0× 10-6/ K

* Alloy: Fe-Ni-Co

* Compound: Mn3AN(C), FeCo(CN)6

* Micro-crystalline glass: Li2O-Al2O3-SiO2

To approach the ZTE

* PTE+NTE

* Adjusting chemical composition

* Controlling magnetic properties

Applications

Mn vacancies and microstructure of ultrafine nanocrystalline in Mn3xCu0.5Ge0.5N

Data of crystal structure derived from Refined refinements for Mn3xCu0.5Ge0.5N

compounds at 295 K (space group: Pm-3m) and the data for the magnetic phase (M1).

Mean grain size (nm) >1000 ~30 ~12

Refined x 1 0.878 0.787

Symbol Mn1000 Mn878 Mn787

a (Å ) at 295 K 3.90077(6) 3.90021(4) 3.89891 (1)

MMn (mB) at Mn site 2.970(5) 2.71(2) 2.22(3)

Mn vacancies and microstructure of ultrafine nanocrystalline in Mn3xCu0.5Ge0.5N

a, Morphology of nanograins. b, Electron diffraction pattern with indexing. c, High resolution transmission electron microscopy of a local region. The arrows represent the orientations of the nanograins. Combining b and c indicates that the ultrafine nanograins have random orientations as a whole. d, Cubic antiperovskite crystal structure. E, M-model.

Data of crystal structure derived from Refined refinements for Mn3xCu0.5Ge0.5N

compounds at 295 K (space group: Pm-3m) and the data for the magnetic phase (M1).

Mean grain size (nm) >1000 ~30 ~12

Refined x 1 0.878 0.787

Symbol Mn1000 Mn878 Mn787

a (Å ) at 295 K 3.90077(6) 3.90021(4) 3.89891 (1)

MMn (mB) at Mn site 2.970(5) 2.71(2) 2.22(3)

Relationships between magnetic moment and lattice constant

c

d

a) Thermal expansion behavior of three materials having different microstructural length scales. b) Magnetic moments of the three materials as a function of temperature. c) Decreases of Mn magnetic moment under high pressure. d) Changes of the temperature dependence of the lattice parameters under high pressure.

Mechanism for the occurrence of ZTE

NTEM and PTET denote NTE caused by magnetic ordering and PTE caused by temperature, respectively, and aM and aT are the corresponding lattice parameters. ΔaM and ΔaT are the changes in the lattice parameter caused by magnetic ordering and temperature, respectively. In the temperature range between T1 and T2 where ΔaM - ΔaT = 0, the ZTE behavior occurs.

What we have Concluded

1. Long-range AFM ordered MNTE-phase possesses the NTE property;

2. Introduction of Zn vacancies induces and stabilizes the MNTE phase;

3. da(MNTE)/dM is nearly constant;

4. TN of MNTE phase can be tuned by chemical substitution;

5. The Mn-site vacancy dominates the degree and rate of the AFM ordering;

6. ZTE can be achieved by adjust the chemical composion.

Magnetocaloric Materials for Commercial Refrigeration

Nd-Fe-B permanent magnet

Magnetocaloric materials

III: Magnetic field

Magnetocaloric

Mn1-xFexP1-yGey Mag. & struct. vs Magnetic field

Lager MCE, small M-field applied, and small hysteresis.

Magnetocaloric Material Mn1.1Fe0.9P1-xGex

Conclusions:

* First order transition

* Large |DSm|

* 150-450 K T-range

* Low cost and non-toxicity

Questions:

* First order transition?

* Why |DSm| is a function

of Magnetic field?

* Maximum the |DSm| ?

* Lowest field?

Solutions:

* Structure vs T & H

* Structure vs |DSm|

|DSm| up to 35 J/kg K

Between 250 and 306 K

Technique:

* Powder diffraction

* Neutron

Intensity map shows that the (001)-PMP intensity decreases

and the (001)-FMP intensity increases as the magnetic field increases,

or temperature decreases.

Is it the firsr-order transition? Mn1-xFexP1-yGey

For comparison, data normalized from the magnetic entropy change |DSm| are shown.

YM01

Conclusion:

1. |DSm| is linearly proportional

to the FM phase fraction.

2. Maximum |DSm| may be larger

than 100 J/kg K.

Questions:

1. 100%PM FM-phase?

2. Minimum M-field?

6

245.4 K/0 T 253.3 K/2 T

PM-phase FM-phase PM-phase FM-phase

Refined Fraction 56.0(1)% 44.0(1)% 66.7(1)% 33.1(1)%

Refined n(P)/n(Ge) 0.78/0.22 0.87/0.13 0.84/0.16 0.75/0.25

a (Å ) 6.0705(1) 6.1515(1) 6.0698(1) 6.1496(2)

c (Å ) 3.4490(1) 3.3592(1) 3.4522(1) 3.3637(1)

Refined parameters for Mn1.1Fe0.9P0.8Ge0.2

a)

b)

Sample may contain small crystallized size particles

Small crystalline size inhibits the magnetic order!

Mn1-xFexP1-yGey

3g site: Mn

3f site: Fe/Fe

We can conclude that

the system is expected to reach:

1. High magnetic entropy Change;

2. Low magnetic field applied;

3. Small hysteresis.

Thanks!