Synchrotron radiation andchemistry

A. Martorana IX School of Synchrotron Radiation, Duino, 17 september 2007

“the branch of science that deals with the identification of the

substances of which matter is composed; the investigation of their

properties and the ways in which they interact, combine, and

change; the use of these processes to form new substances”

What is chemistry?

analysis of the atomic structure analysis of the electronic structure

properties related to the electronic structure structure-properties correlations

synthesis of compounds to investigate how their constituents interact (and eventually determine atomic structure and electronic properties)

Design (and synthesis) of compounds with sought functional properties

what can be done in chemistrywith synchrotron light?

survey of the chemistry proposals of the GILDAbeamline at ESRF

THIN FILMS OF SULFUR-CONTAINING Pd POLY-YNES ON METAL SURFACES:

INTERFACE PROPERTIES STUDIED BY REFLEXAFS

Sensors, optical devices

organic

reflEXAFS

Structural investigation on inorganic-organic thin layers embedding transition metal

oxocluster s

Functional hybrid

organic-inorganic mater

EXAFS

METAL-ORGANIC FRAMEWORKS: IN SITU SYNCHROTRON XRPD STUDY OF

HOST PROPERTIES AS A FUNCTION OF METAL AND TEMPERATURE

Functional materials

Organic

XRD

Gas sensitive Pt containing Organometallic macromolecules: metal - gas interaction studied by EXAFS

Sensors, optical devices

Organic

EXAFS

The hydration process of Ca3SiO5 and Ca2SiO 4 Structural materials XRD

Local environment of zirconium, yttrium and indium in perovskite proton conductor s Solid electrolytes EXAFS, XANES

The role of silver in the synthesis of gold nanorods Functional

nanomaterials inorganic

exafs

Ag site in Ag/Na ion exchanged waveguides: role of the matrix in the tempearture-driven local stress release

Synthesis, functional

mat inorganic

exafs

The role of Ta reticular accommodation and speciation on the electrochemical properties of SnO2-IrO2-Ta2O5 nanostructured composit e s

Electrochemistry, anode

materials inorganic

exafs

In situ powder diffraction study of thermal behaviour of large-porous aluminosilicate ECR-1

Catalysts XRD

A reflEXAFS study of the early stages of solid state reactions: the formation of MnAl2O4 spinel

Fundamental res

Solid state chemistry

reflexafs

Local order and chemical state of Co and Au in field-assisted ion-exchanged gla s s Study of synthesis proc

edure inorganic

EXAFS

2007

Self-assembly and gas storage of nanoporous crystals Functional materials

(organic)

XRD

Study of Br surroundings in supramolecular system formed by cyclodextrin with

indomethacin

Host-guest, pharmac exafs

TEMPERATURE DEPENDENCE OF UNIT CELL PARAMETERS, POLYMORPHISM

AND STRUCTURAL PHASE TRANSITIONS OF ORGANIC SEMICONDUCTORS

Functional materials

(semicond) Organic

xrd

Probing a supramolecular organic zeolite: solvent uptake and release of a

calix[4]dihydroquinone compoun d

Technology of

nanomaterials organic

xrd

Chemical environment and oxidation state of Co ions in CoAl2O4 f i lms Functional materials

inorganic

exafs

The site of Fe in a new magnetic semiconductor: Fe:Ga N Functional materials

Magnetic inorganic

reflexafs

A XANES investigation of rare-earth doped oxide-based phosphors Functional materials

cathodoluminescence

inorganic

exafs

Local environment of barium, cerium and indium in solid-state protonic conductor s Functional materials

electrochemistry

inorganic

exafs

Local environment of barium cerium and gadolinum in the protonic conductor BaCe(1-

x)GdxO(3-d )

Functional materials

electrochemistry

inorganic

exafs xanes

Adsorption of Se/Fe on Imogolite nanotubes: redox reaction s Storage, catalysts etc exafs

EXAFS on Nb-doped magnesium and magnesium hydride: how the Nb-Mg correlation

acts on the hydrogen absorption/desorption process.

Catalysts exafs

THERMAL BEHAVIOUR OF NEW STANNOSILICATE IN THE AS-SYNTHESIZED AND

CATION EXCHANGED FORM S

Catalysts (zeolite) xrd

2006

Pt, Pd AND Zn CONTAINING ORGANOMETALLIC MACROMOLECULES FILMS AT

METAL INTERFACES: REAL AND MODEL SYSTEMS STUDIED BY reflEXAFS

Functional materials

(optical, sensors)

organic

reflexafs

Pd and Zn containing organometallic macromolecules and oligomers: model systems

studied by EXAFS

Functional mat (optical

sensors) organic

exafs

Guest inclusion properties of a novel calix[4]hydroquinone compou n d Functional mat

(storage, sensors..)

organic

xrd

Local structure of liquid gallium in Ga nanoparticles by Ga-K edge EXAFS Fundamental research exafs

POLYMORPHISM, THERMAL EXPANSION, DEHYDRATION AND PHASE

TRANSFORMATION IN TOBERMORITE AND C-S-H MINERALS

Structural materials

cement

xrd

CRYSTAL STRUCTURE, PHASE STABILITY AND DEHYDRATION PROCESS OF

AFM PHASES

Structural materials

(cement)

xrd

Nd localization in Y(3-x)NdxAl5O12 nano-powd e r Functional materials

(optical) inorg

exafs

TIME- RESOLVED POWDER DIFFRACTION AND PDF ANALYSIS OF

NANOCRYSTALLINE TiO2 MATERIALS

Catalysts xrd

GAS ADSORPTION PROCESS OF Ca0.83CuO2 COMPOSITE CRYSTAL: A

STRUCTURAL STUDY BY TIME RESOLVED DIFFRACTION EXPERIMENT

catalysts xrd

Pt and Ru local structure in Pt/Co and Ru/Co bimetallic catalyst catalysts exafs

EXAFS Analysis of Pd-Au resin supported catalysts catalysts exafs

2005

Structural origin of the reactivity of NiO epilayers and nano-powders catalysts exafs

In situ XRD experiments on Ce/Zr mixed oxides TWC catalysts catalysts xrd

EXAFS and XANES studies on silica and alumina supported La, Mn, Co and Fe

oxides catalysts exafs

IN SITU DIFFRACTION STUDY OF THE TRANSFORMATION PROCESS OF

PdO CATALYTIC MATERIALS

catalysts xrd

EXAFS and high resolution XANES study on the coordination and oxidation

changes undergone by Ironspecies in Fe-zeolites upon template removal and

interaction with oxidative/reductive reagents

catalysts exafs

EXAFS and XANES studies on silica and alumina supported perovkite oxides catalysts exafs

Interstitial oxygen in the Nd1.85Ce0.15CuO4+y by polarised Cu-K edge EXAFS Functional materials

(super conductors)

exafs

Fast phase transformation in metastable PbGeO3 by means of XRPD Functional materials

(optics) inorg

xrd

Local Chemical Environment of Ln(III) ions in Lead Germanate Glasses doped

with lanthanides Functional (optics)

inorg

exafs

Study of the local environment around Te and Ta atoms in tellurite glasses with

amounts of tantalium oxide.

Functional materials

(optics) inorg

exafs

Pd AND Pt CONTAINING ORGANOMETALLIC POLYMER FILMS AT

METAL INTERFACES: REAL SYSTEMS STUDIED BY REFLEXAFS

Functional (optics,

coating) organic

reflexafs

Comparison of XAFS and photocurrent generated by monochromatic X-ray

radiation: the case of metal-phthalocyanine layers.

Functional mat

(optics) organic

exafs

Study of ionic solvation sheaths in mixed aqueous/organic solvents Coordination chem exafs

Probing the early stages of solid state reactions with ReflEXAFS fundamental reflexafs

Time-resolved in situ studies of template-directed nucleation and crystallization in

zeolite synthesis from clear solution.

Synthesis control xrd

2001

2007 2006 2005 2001 total

Functional inorganic 4 7 1 4 16

Functional organic 4 4 3 2 13

structural 1 2 3

catalysts 1 3 4 6 14

Basic res (solid state

chem)

2 1 2 5

Basic (solution

chem)

1 1

have been considered:

proposals explicitly declared as belonging to the chemistry area by the

proposers

have not been considered:

environmental, cultural heritage (shared between chemists, geologists,

physicists) (Quartieri)

are not present:

biochemistry (but a significant number of biophysics have been proposed

on the beamline)

techniques not available on the beamline, but of interest for chemical

applications:

single crystal studies, e.g. protein crystallography (Nardini)

photoelectron spectroscopy (Stefani)

small-angle x-ray scattering (Polizzi)

Imaging (Locatelli)

• High-resolution studies

• In situ studies– Chemical environment

– Temperature

• Time-resolved experiments– Slow processes (e.g. diffusion-limited)

– Fast processes (explt time structure of sl)

applications of SL to chemistry described in this talk

Prussian blue Fe4(III)[Fe(II)(CN)6]3

Fe(III)-N-C-Fe(II)

“ The occurrence of negative thermal expansion (NTE) (i.e., when the material

contracts on heating over a certain temperature range) is relatively rare but has

important technological applications….

Even rarer is the occurrence of zero thermal expansion (ZTE)….

Here we report the unexpected finding that isotropic nearly ZTE … in a large

temperature range between 4.2 and 300 K is exhibited by Fe[Co(CN)6]….

The structural properties of Fe[Co(CN)6] were studied as a function of

temperature between 4.2 and 300 K by high-resolution synchrotron X-ray powder

diffraction ”

J. AM. CHEM. SOC. 2004, 126, 15390-15391

Bistability in prussian blue analogues:

spin crossover change of metal-ligand bond length change of ligand conformation

intervalence electron transfer in AM[M’(CN)6]: M(II)-N-C-M’(III) M(III)-N-C-M’(II)

flexibility of the prussian blue framework in accommodating a wide variety of metals and interstitials

ability of the cyanide bridge in mediating charge transferand spin transition

applications as optical switches, magnetic memories etc.

…X-ray photoirradiation can also trigger controllable structural phase

transformations … in the conducting and magnetic properties of selected material

…A substantial advantage of X-ray-induced phototransformations is that the

stimulus can be simultaneously employed as a probe of the changes of matter

…CsFeII[CrIII(CN)6] was recently reported to be the first member of a Prussian

blue analogue series to display … FeII spin crossover (HS,S=2) (LS,S=0)

…Here we show that X-ray light can induce conversion from the HS to the LS

state of the FeII centers

J. AM. CHEM. SOC. 2006, 128, 8358-8363

Fe(II)LS-N 1.9315 Å Cr(III)-C 2.1100 Å

Fe(II)HS-N 2.1153 Å Cr(III)-C 2.1099 Å

X-ray photoelectrons core holes Auger electrons production local lattice deformation Deexcitation into the LS state due to stronger

electron-phonon interaction

Induction time (percolation threshold)

“We report on the first synthesis of Li-intercalated manganese-phthalocyanine (MnPc) in the

bulk form and on the evolution of the structural and magnetic properties as a function of Li

concentration, x.

….Inserted Li+ ions strongly bond to pyrrole-bridging nitrogen atoms of the Pc rings,

thereby disrupting the ferromagnetic Mn-Na….Mn superexchange pathways. This gradually

induces a crossover of the intrachain exchange interactions from ferromagnetic to

antiferromagnetic as the doping level, x, increases coupled with a spin state transition of the

Mn2+ ions from intermediate spin, S =3/2, to high spin, S =5/2”

Lix[MnPc], 0<x<2

Three-way catalysts

NOx

riduzione N

2

CxHy

ossidazione CO

2

COossidazione CO

2

“The main point addressed is the modification of the

oxygen distribution around the metal center in order to

understand how it can influence the oxygen mobility”

“…in situ structural techniques, X-ray absorption

spectroscopy (XAS) and X-ray diffraction (XRD), are

used to investigate the interaction of Pt nanoparticles

with a Ce0.6Zr0.4O2 mixed oxide”

0’30’90’120’

30’60’

60’90’

Reduction of Pt/CeZr by CO

CeZr

Pt/CeZr

C e r i u m P l a t i n u m ( 1 / 5 )

Pt5Ce alloy

anode 2H2 4H+ + 4e-

cathode O2 + 4e- + 4H+ 2H2O

How a fuel cell works

Perovskite (CaTiO3) structure

“The local structure of yttrium in Y-doped BaCeO3 compounds was

studied using X-ray absorption spectroscopy (XAS) at the Y K-

edge…In situ measurements performed in O2/H2O flux show that …the

observed significative structural changes …point out a preferential

insertion of the hydroxyls around the dopant in the Y-doped BaCeO3

compounds.

“Solvation dynamics, the process of solvent shell reorganization

upon electronic structure changes in a solute, is one of the most

studied processes in chemical dynamics. This is based on its

importance in liquid phase chemistry and in biology, where the

solvent shell has an active role in assisting, hindering, or triggering

chemical reactions”