Outline

1
Outline

• Introduction (physical background)
• Magic Angle Spinning
• Advanced Pulse Techniques
• Applications
• Instrument Setup
• Measurements

2
Applications

• Polymers
• Glasses
• Porous materials
• Liquid crystals

3
Schematic of a typical semicrystalline linear
polymer
4
Stereochemical issue in substituted polymers
5
Signature of stereoregularity in the solid state
spectrum
6
Static 2D exchange spectrum for polyethyleneoxide
(PEO)
Experiment Simulation
7
3D static 13C exchange spectra of
polyethyleneoxide polyvinylacetate
8
Applications

• Polymers
• Glasses
• Porous materials
• Liquid crystals

9
Static whole-echo 207Pb NMR spectrain
Pb-silicate glasses
mol PbO 66 50.5 31
Linewidth 400 kHz _at_ 9.4 T signals of 6
experiments summed up
4000 0 -4000 ppm
10
Sodium silicate glasses
Static 17O NMR spectra bridging (BO)
and non-bridging (NBO) oxygens
Na2Si2O5 Na2Si3O7 Na2Si4O9
NBO
BO
600 0 -600 ppm
11
Structure of glasses (I)
NBO
BO
12
29Si NMR spectra for sodium silicate glasses
static MAS
Q4
mole Na2O 34 37 41
Q3
Q2
Q3 Q2
0 -100 -200 ppm -60 -80 -100
13
Structure of glasses (II)
Q4
Q2
Q3
Q1
14
1H-29Si CPMAS intensity as a function of contact
time
Q2 Q3 Q4
Different sites in a Na2Si4O9 glass with 9.1 wt
H2O
0 20 40 contact time (ms)
15
Efficiency for (1H? 29Si)-CP
Acquisition
29Si
CP
decoupling
1H
t
16
29Si MAS NMR spectra for a CaSi2O5 glass
SiO4 SiO5 SiO6
x 8 glass crystal
quenched from a10 GPa pressure meltisotopically
enriched high pressure phasenormal isotopes
-50 -100 -150 -200 ppm
17
11B MAS NMR spectra for a sodium borate glass
(with 5 mole Na2O)
data fit
slow cooled fast cooled
R
BO4
NR
30 15 0 ppm
data fit
R
BO4
NR
18
31P MAS NMR spectra for sodium phosphate glasses
mol Na2O 56 53 40 30 15 5
Q1 Q2
Q3
100 0 -100 ppm
19
31P double-quantum NMR spectrum
Q2
Q1
-60
2-2
Double-quantum dimension (ppm)
1-2
2-1
1-1
0
0 -30
Single-quantum dimension
20
1H MAS NMR spectrum for a GeO2-doped silica glass
loaded with H2 and UV-irradiated after
subtraction of intense back- ground signal
SiOH GeOH
GeH
9.4 T, 10 kHz spinning
12 6 0 -6 ppm
Sample contains 8 1019 H atoms/cm3(correspondin
g to about 500 ppm of H2O)
21
17O 3QMAS NMR spectrum for a glass on the
NaAlO2-SiO2 join with Si/Al 0.7
-50 0 50 100
MAS dimension (ppm)
Al-O-Al
Si-O-Al
0 -10 -20 -30 -40 -50
Isotropic dimension (ppm)
22
17O 3QMAS NMR spectrum for a borosilicate
-100 -50 0 50 100
B-O-B
MAS dimension (ppm)
Si-O-Si
Si-O-B
-25 -50 -75 -100
Isotropic dimension (ppm)
23
11B-27Al CP-HETCOR NMR spectrum
BO4
BO3
-80 0 80
AlO6
AlO5
AlO4
40 20 0 -20 ppm
24
Applications

• Polymers
• Glasses
• Porous materials
• Liquid crystals

25
Porous materials
Zeolite A
Sodalite
26
Porous materials
Faujasite
Cancrinite
27
Porous materials
Zeolite ZK-5
Zeolite Rho
28
Zeolite framework projections
AlPO4-5 along 001
AlPO4-11 along 100
VPI-5 along 001
29
High-resolution 29Si MASNMR spectra of
syntheticNa-X and Na-Y zeolites
2
(Si/Al) 1.03 1.19 1.35 1.59 1.67 1.87
2.00 2.35 2.56 2.61 2.75
3
1
4
0
4
3
n
Si(nAl) lines
2
1
0
-80 -90 -100 -110 -80 -90 -100 -110
30
Possible ordering schemes for zeolite Y
Si/Al 1.67
Intensity ratios Si(4Al)Si(3Al)Si(2Al)Si(1Al)
Si(0Al)
Si
Al
31
29Si MAS NMR spectrum of highly siliceous
mordenite
3
2
1
Intensities
-110 -112 -114 -116 -118
ppm
32
Mordenite structure along 001
T-site No. per unit cell Neighbouring sites Mean
T-O-T bond angle T1 16 T1, T1, T2,
T3 150.4 T2 16 T1, T2, T2, T4 158.1 T3 8 T1,
T1, T3, T4 153.9 T4 8 T2, T2, T3, T4 152.3
33
Mordenite structure along 001
T1/T3/T2T4 3 cross peaks T1/T4/T2T3 2 cross
peaks T2/T3/T1T4 2 cross peaks T2/T4/T1T3 3
cross peaks
T-site No. per unit cell Neighbouring sites Mean
T-O-T bond angle T1 16 T1, T1, T2,
T3 150.4 T2 16 T1, T2, T2, T4 158.1 T3 8 T1,
T1, T3, T4 153.9 T4 8 T2, T2, T3, T4 152.3
34
29Si MAS NMR spectrum of highly siliceous
mordenite
T2 T4
T1
T3
J-scaled COSY spectrum
T1/T3/T2T4 3 cross peaks T1/T4/T2T3 2 cross
peaks T2/T3/T1T4 2 cross peaks T2/T4/T1T3 3
cross peaks
-110 -112 -114 -116 -118
ppm
35
29Si MAS NMR spectra of ultrastabilized and
hydrothermally realuminated zeolites
2
1
Si/Al 2.56
3
0
4.96 4.26 7.98 2.44 2.70 2.09
-80 -90 -100 -110 -120 -90
-100 -110 -120 -90 -100 -110
ppm
36
Chemical reactions in zeolites
1000 C
C H2O CO H2 (water gas reaction)
37
Chemical reactions in zeolites
1000 C
C H2O CO H2 (water gas reaction) .
x O2 (n-x) CO n H2 x CO2 (water gas
shift)
38
Chemical reactions in zeolites
1000 C
C H2O CO H2 (water gas reaction) .
x O2 (n-x) CO n H2 x CO2 (water gas
shift) CO 2 H2 CH3OH (conversion of
synthesis gas)
catalyst
39
Chemical reactions in zeolites
1000 C
C H2O CO H2 (water gas reaction) .
x O2 (n-x) CO n H2 x CO2 (water gas
shift) CO 2 H2 CH3OH (conversion of
synthesis gas) CH3OH CH3OH CH3OCH3
catalyst
Zeolites 150 C
40
Chemical reactions in zeolites
1000 C
C H2O CO H2 (water gas reaction) .
x O2 (n-x) CO n H2 x CO2 (water gas
shift) CO 2 H2 CH3OH (conversion of
synthesis gas) CH3OH CH3OH
CH3OCH3 .. complex mixture of hydrocarbons
catalyst
Zeolites 150 C
Zeolites 300 C
41
Chemical reactions in zeolites
1000 C
C H2O CO H2 (water gas reaction) .
x O2 (n-x) CO n H2 x CO2 (water gas
shift) CO 2 H2 CH3OH (conversion of
synthesis gas) CH3OH CH3OH
CH3OCH3 .. complex mixture of hydrocarbons
catalyst
Zeolites 150 C
Zeolites 300 C
42
13C MAS NMR spectrum of H-ZSM-5 with 50 torr of
adsorbed MeOH heated to 300 C for 35 mins
0 -5 -10 -15
40 30 20 10
0 -10 ppm
43
13C MAS NMR spectrum of H-ZSM-5 with 50 torr of
adsorbed MeOH heated to 300 C for 35 mins
scalar coupling
0 -5 -10 -15
1JCH 125 Hz
a quintet with ratio 14641 is expected for
methane
40 30 20 10
0 -10 ppm
44
Heteronuclear 2D J-resolved 13C MAS NMR spectrum
300 200 100 0 Hz -100 -200 -300
26 24 22 18 17 16
15 -11 -12 ppm
45
13C NMR spin diffusion spectrum of products of
methanol conversion over zeolite ZSM-5
25 20 15 10 ppm
46
13C MAS NMR spectrum of H-ZSM-5 with 50 torr of
adsorbed MeOH heated to 300 C for 35 mins
Methane Ethane Propane Cyclopropane n-Butane Isobu
tane (n-Pentane) Isopentane n-Hexane n-Heptane
0 -5 -10 -15
40 30 20 10
0 -10 ppm
47
Methylated aromatic products

CO




190 185 180 140 135 130 125
ppm
48
129Xe NMR as a sensitive tool for materials
0 reference S surface collisions Xe Xe-Xe
collisions E electric field effect M paramagneti
c species
49
129Xe as a sensitive probe for various zeolites
ZK4
ZSM-5
1021
NaY
ZSM-11
K - L
Xe atoms /g
omega
1020
60 80 100 120 140 ppm
50
Applications

• Polymers
• Glasses
• Porous materials
• Liquid crystals

51
Graphitic nanowires
Hexa-peri-hexabenzocoronene (HBC)
52
HBC monolayer on HOPG
53
Phase transitions of alkyl substituted HBC
54
Temperature dependence of the one dimensional
charge carrier mobility
55
Liquid crystalline (dichotic) behaviour ofalkyl
substituted HBCs
R C12H25 Hexadodecyl-hexa-peri-hexabenzocoronene
(HBC-C12)
56
Charge carrier mobility in HHTT
57
1H DQ MAS NMR spectra of HBC-C12
a-deuterated fully protonated
58
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59
Proposed stacking model based on solid state NMR
60
Graphitic stacking
61
Spinning side band simulation in the DQ time
domain
For an isolated spin pair, using N cycles of the
recoupling sequence for both the excitation and
reconversion of DQCs, the DQ time domain signal
is given by
b and g are Euler angles relating the PAF of the
diploar coupling tensor to the rotor fixed
reference frame
with
- distance information in a rigid system, or
indication of mobility
Ref. Graf et al. J. Chem. Phys. 1997, 106, 885
62
Homonuclear correlation between I 1/2 spins
63
aromatic protons at 8.3 ppm (crystalline phase)
DQ spinning side band patterns
wR 35 kHz
aromatic protons at 6.2 ppm (LC phase)
wR 10 kHz
aliphatic protons at 1.2 ppm (crystalline phase)
wR 35 kHz
fitted dipolar coupling constants
64
Effect of additional phenyl spacers
R -C12H25 or -C6H4-C12H25
65
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66
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67
Space filling model for HBC-PhC1
68
X-ray diffraction patterns of the mesophases