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Chapter 18 Introduction to Solid State NMR 18.0 Summary of internal interactions in solid state NMR 18.1 Typical lineshapes for static samples 18.2 Magic-angle-spinning.

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Presentation on theme: "Chapter 18 Introduction to Solid State NMR 18.0 Summary of internal interactions in solid state NMR 18.1 Typical lineshapes for static samples 18.2 Magic-angle-spinning."— Presentation transcript:

1 Chapter 18 Introduction to Solid State NMR 18.0 Summary of internal interactions in solid state NMR 18.1 Typical lineshapes for static samples 18.2 Magic-angle-spinning (MAS) 18.3 Cross polarization (CP) and CPMAS 18.4 Homonuclear decoupling pulse sequences 18.5 Recoupling (CSA and dipolar) 18.6 Multi-quantum MAS (MQMAS) of quadrupole spins 18.7 Applications

2 High resolution solid state NMR Recoupling (Secoupling) Resolution gap between LSNMR and SSNMR: still large but decreasing “Solid NMR” in chemistry and condensed matter physics can be very different (the later normally uses conducting samples that contain large Knight shift)

3 Single Crystal or Polycrystalline (Powder) Samples

4 Review of Lecture 9 for the summary of the four major interactions in NMR spectroscopy.

5 Magic Angle Spinning (MAS) B0B0 Θ=54.74 °

6

7 Coordinate Systems

8 Z X Y

9 Coordinate Systems Lab Frame(XYZ) Molecular frame (may be a PAS of certain interaction tensor) β

10 How to calculate a solid NMR spectrum More generally,

11 Sensitivity High Fields Labeled samples CP CPMAS

12 Cross polarization  CPMAS─one of the most important solid state NMR techniques. CP contact time: several hundred microseconds to tens of milliseconds. Purpose: To enhance the sensitivity of the lower γ spins such as carbon-13. maximal enhancement factor: γI/γS Other advantages: Shorter recycle delay time Distinguish the interconnectivity of nuclear spins such as the protonation of a certain carbon nucleus.

13

14 1H-13C CPMAS spectrum of (a) mixed lactose, (b) -lactose and (c) anhydrous stable -lactose. The lines marked by asterisks are assigned to the residual amorphous lactose

15 Sodium silicate glasses BO NBO Na 2 Si 2 O 5 Na 2 Si 3 O 7 Na 2 Si 4 O ppm Static 17 O NMR spectra bridging (BO) and non-bridging (NBO) oxygens

16 Structure of glasses (I) BO NBO

17 29 Si NMR spectra for sodium silicate glasses staticMAS Q4Q4 Q 3 + Q ppm mole % Na 2 O Q2Q2 Q3Q3

18 Structure of glasses (II) Q4Q4 Q2Q2 Q1Q1 Q3Q3

19 1 H- 29 Si CPMAS intensity as a function of contact time Different sites in a Na 2 Si 4 O 9 glass with 9.1 wt% H 2 O Q2Q3Q4Q2Q3Q contact time (ms)

20 Ramp CP (Matching Condition Satisfied at High Speeds) CPdecoupling 1H1H1H1H X Acquisition

21 Comparison of standard and ramp-CP Carbonyl-signal of glycine (nat. abundance), rot = 20 kHz, as function of 1 H-power rectangle ramp

22 Double-CP X Acquisition CP 1 Decoupling 1H1H1H1H CP 2 Y Avoid CP

23 H-N-C Double- CPMAS: Spectral Simplification (A) CP-MAS 13C NMR spectrum and (B) 15N-13C double- CP/MAS NMR data of the [13C6,15N3]-His labeled LH2 complex, measured at 220 K by using a wide-bore 750 NMR spectrometer. The spinning rate around the magic angle was kept at 12 kHz. Each spectrum represents about scans collected with an acquisition time of 8 ms and a recycle time of 2 s. The spectra are normalized at the α’ peaks. de Groot et al., JACS 123,4203(2001).

24 Shielding electronic shieldinginduced magnetic field B loc = B 0 – B i = B 0 (1 – s)

25

26 Shielding Tensor: Decomposed Theoretically, CSA tensor contains anti-symmetric components, but the experimental evidence has been rather weak. It remains an interesting topic in fundamental NMR research.

27 (Static) Powder Patterns

28 Powder spectrum  iso, δ, 

29 Magic-Angle-Spinning Spectrum

30 MAS for spin 1/2 nuclei

31

32 Total Suppression of Spinning Side Bands (TOSS)

33 TOSS Example

34 Proton NMR spectra of a water and hexadecane mixture in a sample of packed glass beads.

35 The Quadrupolar Majority

36 First and Second Order Quadrupolar Hamiltonains

37 Experimental (A) and simulated (B and C) 2H MAS NMR spectra (14.1 T) of KD2PO4 using ω r = 7:0 kHz. The simulated spectrum in (B) employs the optimized 2H quadrupole coupling and CSA parameters listed below whereas the simulation in (C) only considers the quadrupole coupling interaction. The asterisk indicates the isotropic peak. 2 H MAS HZHZ H Z + H Q H Z + H Q (powder)

38 Half-Integer Quadrupolar Spins: Central Transtion A few hundred Hz to several kHz

39 Satellite Transitions Static MAS Hundreds kHz to a few MHz!

40 23 Na ( MHz) NMR spectra of NaN03 recorded using (a) static and (b) MAS (v, = 4820 Hz) conditions ( 16 scans). The central transition is cut off at (a) 1/4 and (b) 1/13 of its total height. Spin-3/2

41 JORGEN SKIBSTED, NIELS CHR. NIELSEN, HENRIK BILDME, HANS J. JAKOBSEN, JMR, 95, 88(1991)

42 27 AI ( MHz) MAS NMR spectra of the central and satellite transitions for α- Al2O3. The ppm scale is referenced to an external sample of 1.0 M AlCl3, in H2O. (a) Experimental spectrum showing the relative intensities of the central and satellite transitions and observed using a Varian VXR-400 S wideline spectrometer; ω r = 7525 Hz, spectral width SW = 1.0 MHz, pulse width pw = 1.0 μ s ( π /4 solid pulse), and number of transients nt= (b) Spectrum in (a) with the vertical scale expanded by a factor of ten; the inset shows expansion of a region where the second-order quadrupolar shift between the (±5/2, ±3/2) and the (±3/2, ±1/2) satellite transitions is clearly observed (see text). (c) Simulated MAS spectrum for the satellite transitions in (b) obtained using QCC = 2.38 MHz, η = 0.00, ω r = 7525 Hz, and Gaussian linewidths of 900 and I 175 Hz for the (±3/2, ±1/2) and (±5/2, ±3/2) transitions. respectively. HANS J. JAKOBSEN, JORGEN SKIBSTED, HENRIK BILDSBE, ANDNIELS CHR.NIELSEN,JMR 85,173(1989) Spin-5/2

43 51 V MAS (H Q +H CSA ) Question: is it possible to suppress the sidebands of a satellite transition MAS spectrum? “Answer”: Not done yet, but it’s an interesting topic.

44

45 Direct Dipole-Dipole Coupling

46

47 Dipolar Coupling

48 Direct Dipole-Dipole Coupling Spin Pair ~80 kHz Many coupled spins

49 Homogeneous Interaction (Homonuclear Dipolar Interaction): All Spins Are Coupled to Each Other

50 Decoupling Sequences Hetronuclear decoupling: CW TPPM XiX COMORO SPINAL SDROOPY,eDROOPY,DUMBO, eDUMBO, eDUMBO lk Homonuclear decoupling WAHUHA Lee-Goldburg (LG and variants: FSLG, PMLG,wPMLG) MREV-8 BR-24 BLEW-12 CORY-24 TREV-8 MSHOT-3 DUMBO, eDUMBO, eDUMBO lk, CNn v, RNn v

51 Decoupling sequences: TPPM TPPM = Two Pulse Phase Modulation Pulse length:  p    -  :   0 – 0.6  s, optimize! Phaseshift:   , evt. optimize!

52 TPPM- decoupling, optimize t p optimum pulse length:  p = 2.9  s, (    s) C  -signal in Glycine C- 15 N, rot = 30 kHz,  = 15° p/sp/s dec = 150 kHz dec = 150 kHz

53 XiX - decoupling XiX= X Inverse X Pulse length:  p = x ·  R, x  n, but x  n,... (recoupling at (n/4)  R )optimize! nRnRnRnR t

54 XiX- decoupling, optimize  p C  -signal of glycine C- 15 N, rot = 30 kHz, dec = 150 kHz dec = 150 kHz

55 Comparison of decoupling methods C  -signal of glycine C- 15 N, dec = 150 kHz TPPM (15°)CWXiX 10 kHz 30 kHz

56 Decoupling methods: π-pulse decoupling Rotorsynchronised train of 180°-pulses xy-16-phase cycle for large band width RRRR t xy-16-phase cycle: 0–90–90–0–0–90–90–0–180–270–270–180– 180–270–270–180

57 π-pulse decoupling for 19 F 19 F: Dipol-Dipol-coupling spun out at fast rotation but: large chemical shift anisotropy but: large chemical shift anisotropy  large band width important 19 F-spectrum of teflon at 30 kHz

58 π-pulse-decoupling for 19 F 13 C{ 19 F}-CP/MAS-spectrum of Teflon, rot = 30 kHz CW TPPM 15°  -pulse

59 Pulsed (homonuclear) decoupling WAHUHA Lee-Goldburg (LG and variants: FSLG, PMLG, wPMLG) MREV-8 BR-24 BLEW-12 CORY-24 TREV-8 MSHOT-3 DUMBO, eDUMBO, eDUMBO lk, CNn v, RNn v

60 Lee-Goldburg (LG) Series LG: Magic-angle-spinning in spin space (Magic Sandwich) [] n * X Y Z o ω rf ΔωΔω [] n * Frequency-Switched LG (windowed) Phase-Modulated LG

61 TREV-8 [] n *

62 MSHOT (Magic Sandwich High Order Terms Decoupling)

63 MSHOT Malonic Acid M. Hohwy and N. C. Nielsen, J. Chem. Phys. 106, 7571 (1997). M. Hohwy, P. V. Bower, H. J. Jakobsen, and N. C. Nielsen, Chem, Phys. Lett. 273, 297 (1997) M. Hohwy, J. T. Rasmussen, P. V. Bower, H. J. Jakobsen, and N. C. Nielsen J. Magn. Reson. 133,374(1998). KHSO 4 Ca(OH) 2

64 MSHOT-3-CRAMPS (combination of rotation and multi-pulse spectroscopy

65 PMLG, wPMLG

66 wPMLG: Example The one-dimensional proton spectra of (a) U–15N–DL-alanine, (b) monoethyl fumarate, (c) glycine and (d) U–13C –15N–histidineHClH2O, detected during wPMLG-5 at a spinning frequency of 14.3 kHz and a Larmor frequency of 300 MHz. The length of the detection windows was 3.2 μ s and that of the PMLG pulses was 1.7 μ s.

67 2D proton–proton correlation spectra of U–13C–histidineHClH2O, obtained using the pulse sequence shown at the top, with mixing times of (a) 200 μs and (b) 500 μs. The F1 (vertical) and F2 (horizontal) proton spectra are skyline projections of the 2D spectra. These experiments were performed at a spinning frequency of kHz and a Larmor frequency of 300 MHz. During the PMLG-9 and wPMLG-5 irradiation the pulse lengths were 1.1 and 1.7 μs, respectively. The length of the detection windows during wPMLG-5 was 3.2 μs.

68 2D carbon–proton correlation spectra of U–13C–histidineHClH2O, obtained using the pulse sequence shown at the top, with Lee–Goldburg CP mixing times of (a) 80 μs and (b) 3 ms. The F1 (vertical) carbon and F2 (horizontal) proton spectra are skyline projections of the 2D spectra. These experiments were performed at a spinning frequency of kHz and a Larmor frequency of 300 MHz. During the wPMLG-5 irradiation the pulse lengths were 1.7 μs and the length of the detection windows was 5.1 μs.

69 FSLG for Heteronuclear Decoupling CH CH 2

70 Pulsed (homonuclear) decoupling (WAHUHA (WHH4), MREV-8) P. MANSFIELD, M. J. ORCHARD, D. C. STALKER, AND K. H. B. RICHARDS, Phys. Rev. B 7, 90 (1973). W. K. RHIM, D. D. ELLEMAN, AND R. W. VAUGHAN,.I. Chem. Phys. 59, 3740 (1973). W. K. RHIM, D. D. ELLEMAN, L. B. SCHREIBER, AND R. W. VAUGHAN, J. Chem. Phys. 60, 4595 ( 1974). J. S. WAUGH, L. HUBER, AND U. HAEBERLEN, Phys. Rev. Lett. 20, 180 (1968). [] n *

71 BR-(24,48,52) D. P. BURUM AND W. K. RHIM, J. Chem. Phys. 71, 944 (1979). [] n *

72 BLEW-(12,48) D. P. BURUM,* M. LINDER, AND R. R. ERNST, J. MAGN. RESON. 4, (1981) [] n *

73 CORY-24 [] n *

74 eDUMBO (experimental Decoupling Using Mind-Boggling Optimization) H rf =ω 1 [I x cosψ(t)+I y sinψ(t)] MAS rate = 22 kHz

75 DUMBO and eDUMBO Flow diagrams illustrating (a) the DUMBO and (b) the eDUMBO approaches to developing improved decoupling schemes.

76 Symmetry Based Decoupling Pulse Sequences [] n *

77 Indirect Spin-Spin Coupling

78

79 Dipolar-Chemical Shift NMR (1D) The interplay of chemical shift anisotropy and spin- spin coupling interactions results in complex line shapes. The dipolar-chemical shift method is useful in the case of isolated spin pairs. Many other cases where more than one interaction are involved.

80 Multidimensional Approaches Separation of Local Fields (Correlation) MQC-SQC Correlation

81 Separation of Local Fields Chemical shift correlation Chemical shift -dipolar correlation Chemical shift-quadrupolar correlation t1t1 tmtm t2t2 I S Interaction A Interactions B(+A) Mixing

82 Homonuclear correlation : establishing connectivities

83 Dipolar - Chemical Shift Correlation

84 Dipolar Coupling

85 Measuring dipolar coupling constants

86 Homonuclear correlation between I = 1 / 2 spins

87 Double/single quantum correlation

88 Homonuclear double/single-quantum correlation

89 MQMAS

90 Under rapid magic angle spinning (MAS):

91 Lineshape of half-integer quadropolar nuclei static MAS

92 Dig EFGs From This Spectrum! Energy Levels of a Spin-3/2 Nucleus in a Static Magnetic Filed m 3/2 1/2 -1/2 -3/2 ZeemanQuadrupolar (first-order) Quadrupolar (second- order) Quadrupolar Coupling May Be Very Strong! Multiple Sites Multiple Sites In A Powder

93 Both The EFG Information And High Resolution Can Be Achieved. Second Order Quadrupolar Frequency 2D Solution:Keep AND Remove

94 θM θM MQC SQC Magic Angle (54.7 ) Spinning o Multi-Quantum Magic-Angle Spinning (MQMAS)

95 Multiple quantum selection : phase cycles (i) direct method (ii) indirect method

96 L.Frydman, J.S.Harwood, JACS, 1995.

97 17 O-MQMAS spectrum of the silicate coesite

98 MQMAS Signal Enhancement RIACT QCPMG Shaped Pulses FASTER SPAM + STMAS …

99

100 What MQMAS Tells And Does Not Tell Three Principal Values—Yes! Plus Isotropic Chemical Shift V 33 V 22 V 11 X Y Z Orientation—No For Powder Samples Used

101 The Relative Orientation Between Two Quadrupolar Tensors The Relative Orientation Between Two Quadrupolar Tensors What MQMAS May Tell V 33,B YBYBYBYB V 33,A V 11,A XAXAXAXA YAYAYAYA V 11,B V 22,A V 22,B XBXBXBXB ZAZAZAZA ZBZBZBZB

102 Relative Orientation Is The Same For All Crystallites In A Powder Sample EFG Tensor of Spin A EFG Tensor of Spin B

103 MQMAS Spin Diffusion/Exchange Pulse Sequence P 1 t 1 P 2 t m P 3 t 2 P 1 t 1 P 2 t m P 3 t 2 MQC of Spin A(B) SQC of Spin B(A) A(3/2,-3/2)  B(1/2,-1/2) Scheme

104 Two Spin-3/2 MQMAS-Spin Diffusion Spectrum MQMAS Peaks Cross Peaks (3/2,-3/2)  (1/2,-1/2) Ding Lab

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106 3D CSA-D Correlation (with One Quadrupolar Spin) J. Grinshtein, C. V. Grant, L. Frydman, J Am Chem Soc 124,13344(2002). Six nonequivalent Na sites are resolved.

107 Recoupling High resolution achieved with MAS sacrifices information on anisotropy. Anisotropy can be recovered with recoupling Selective and broadband recoupling CSA recoupling and dipolar recoupling

108 CSA Recoupling Off magic angle spinning Stop and go (STAG) Magic-angle-hopping (MAH) Switching-angle-spinning (SAS) or Dynamic-angle-spinning (DAS) Magic-angle-turning (MAT) (SPEED)

109 Dipolar Recoupling SEDOR REDOR DRAMA (DRAW) TRAPDOR REAPDOR C7

110 Dipolar recovery at the magic angle (DRAMA)

111 Full DRAMA sequence

112 Zero and double quantum coherence

113 Double quantum filtered experiments

114 The C7 recoupling sequence

115 Rotational resonance experiment

116 Data resulting from rotational resonance

117 Heteronuclear correlation : general spin-echo sequence

118 Spin-echo double resonance experiment (SEDOR)

119 The REDOR experiment

120 Transfer of population in double resonance (TRAPDOR )

121 Adiabatic zero crossing

122 REAPDOR sequence for measuring dipolar couplings between I ≥ 1 and I = 1 / 2 spins

123 Example of relaxation: dipolar relaxation

124 How does the magnetization relax back to equilibrium after applying a radiofrequency pulse?

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128 How does the spectra density J depend on the correlation time?

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130 In the extreme narrowing limit (very fast motion and very short correlation time), the following holds.

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134 Other Topics Multiple pulse for homonuclear decoupling (WAHUHA, MREV, HR, CORY etc) Combination of rotation and multiple pulses (CRAMP) Recoupling (Rotational Resonance, REDOR, RFDR etc) Other multi-dimensional solid state NMR (HETCOR, CSA/Q correlation, D/Q correlation, 3D correlation spectra) Single-Crystal NMR

135 Applications Polymers Glasses Porous materials Liquid crystals

136 Schematic of a typical semicrystalline linear polymer

137 Stereochemical issue in substituted polymers

138 Signature of stereoregularity in the solid state spectrum

139 Static 2D exchange spectrum for polyethyleneoxide (PEO) ExperimentSimulation

140 3D static 13 C exchange spectra of polyethyleneoxide polyvinylacetate

141 Applications Polymers Glasses Porous materials Liquid crystals

142 Static whole-echo 207 Pb NMR spectra in Pb-silicate glasses mol % PbO ppm Linewidth ~ T —> signals of 6 experiments summed up

143 Sodium silicate glasses BO NBO Na 2 Si 2 O 5 Na 2 Si 3 O 7 Na 2 Si 4 O ppm Static 17 O NMR spectra bridging (BO) and non-bridging (NBO) oxygens

144 Structure of glasses (I) BO NBO

145 29 Si NMR spectra for sodium silicate glasses staticMAS Q4Q4 Q 3 + Q ppm mole % Na 2 O Q2Q2 Q3Q3

146 Structure of glasses (II) Q4Q4 Q2Q2 Q1Q1 Q3Q3

147 1 H- 29 Si CPMAS intensity as a function of contact time Different sites in a Na 2 Si 4 O 9 glass with 9.1 wt% H 2 O Q2Q3Q4Q2Q3Q contact time (ms)

148 Efficiency for ( 1 H  29 Si )-CP CPdecoupling 1H1H1H1H 29 Si Acquisition 

149 29 Si MAS NMR spectra for a CaSi 2 O 5 glass x 8 glass crystal SiO 4 SiO 5 SiO ppm quenched from a 10 GPa pressure melt isotopically enriched high pressure phase normal isotopes

150 11 B MAS NMR spectra for a sodium borate glass ppm data fit data fit R BO 4 NR R slow cooled fast cooled (with 5 mole% Na 2 O)

151 31 P MAS NMR spectra for sodium phosphate glasses mol % Na 2 O ppm Q1Q2Q1Q2 Q3Q3

152 31 P double-quantum NMR spectrum Double-quantum dimension (ppm) Single-quantum dimension Q1Q1 Q2Q2

153 1 H MAS NMR spectrum for a GeO 2 -doped silica glass loaded with H 2 and UV-irradiated after subtraction of intense back- ground signal GeH SiOH + GeOH ppm Sample contains ~8  H atoms/cm 3 (corresponding to about 500 ppm of H 2 O) 9.4 T, 10 kHz spinning

154 17 O 3QMAS NMR spectrum for a glass on the NaAlO 2 -SiO 2 join with Si/Al = 0.7 MAS dimension (ppm) Isotropic dimension (ppm) Al-O-Al Si-O-Al

155 17 O 3QMAS NMR spectrum for a borosilicate Si-O-Si Si-O-B B-O-B MAS dimension (ppm) Isotropic dimension (ppm)

156 11 B-{ 27 Al} CP-HETCOR NMR spectrum BO 4 BO 3 AlO 6 AlO 4 AlO ppm

157 Applications Polymers Glasses Porous materials Liquid crystals

158 Porous materials Sodalite Zeolite A

159 Porous materials FaujasiteCancrinite

160 Porous materials Zeolite ZK-5Zeolite Rho

161 Zeolite framework projections AlPO 4 -5 along [001] AlPO along [100] VPI-5 along [001]

162 High-resolution 29 Si MAS NMR spectra of synthetic Na-X and Na-Y zeolites (Si/Al) = n =Si(nAl) lines

163 Possible ordering schemes for zeolite Y Si/Al = 1.67 Si Al Intensity ratios: Si(4Al):Si(3Al):Si(2Al):Si(1Al):Si(0Al)

164 29 Si MAS NMR spectrum of highly siliceous mordenite ppm Intensities

165 Mordenite structure along [001] T-siteNo. per unit cellNeighbouring sitesMean T-O-T bond angle T116T1, T1, T2, T3150.4° T216T1, T2, T2, T4158.1° T38T1, T1, T3, T4153.9° T48T2, T2, T3, T4152.3°

166 Mordenite structure along [001] T-siteNo. per unit cellNeighbouring sitesMean T-O-T bond angle T116T1, T1, T2, T3150.4° T216T1, T2, T2, T4158.1° T38T1, T1, T3, T4153.9° T48T2, T2, T3, T4152.3° T1/T3/T2+T4 : 3 cross peaks T1/T4/T2+T3 : 2 cross peaks T2/T3/T1+T4 : 2 cross peaks T2/T4/T1+T3 : 3 cross peaks

167 29 Si MAS NMR spectrum of highly siliceous mordenite J-scaled COSY spectrum ppm T1 T3 T2 + T4 T1/T3/T2+T4 : 3 cross peaks T1/T4/T2+T3 : 2 cross peaks T2/T3/T1+T4 : 2 cross peaks T2/T4/T1+T3 : 3 cross peaks

168 29 Si MAS NMR spectra of ultrastabilized and hydrothermally realuminated zeolites Si/Al = ppm

169 Chemical reactions in zeolites {C} + H 2 OCO + H 2 (water gas reaction) 1000 °C

170 Chemical reactions in zeolites {C} + H 2 OCO + H 2 (water gas reaction) ……. + x O 2 (n-x) CO + n H 2 + x CO 2 (water gas shift) 1000 °C

171 Chemical reactions in zeolites {C} + H 2 OCO + H 2 (water gas reaction) ……. + x O 2 (n-x) CO + n H 2 + x CO 2 (water gas shift) CO + 2 H 2 CH 3 OH(conversion of synthesis gas) 1000 °C catalyst

172 Chemical reactions in zeolites {C} + H 2 OCO + H 2 (water gas reaction) ……. + x O 2 (n-x) CO + n H 2 + x CO 2 (water gas shift) CO + 2 H 2 CH 3 OH(conversion of synthesis gas) CH 3 OHCH 3 OH + CH 3 OCH °C catalyst Zeolites 150 °C

173 Chemical reactions in zeolites {C} + H 2 OCO + H 2 (water gas reaction) ……. + x O 2 (n-x) CO + n H 2 + x CO 2 (water gas shift) CO + 2 H 2 CH 3 OH(conversion of synthesis gas) CH 3 OHCH 3 OH + CH 3 OCH 3 ……..complex mixture of hydrocarbons 1000 °C catalyst Zeolites 150 °C Zeolites 300 °C

174 Chemical reactions in zeolites {C} + H 2 OCO + H 2 (water gas reaction) ……. + x O 2 (n-x) CO + n H 2 + x CO 2 (water gas shift) CO + 2 H 2 CH 3 OH(conversion of synthesis gas) CH 3 OHCH 3 OH + CH 3 OCH 3 ……..complex mixture of hydrocarbons 1000 °C catalyst Zeolites 150 °C Zeolites 300 °C

175 13 C MAS NMR spectrum of H-ZSM-5 with 50 torr of adsorbed MeOH heated to 300 °C for 35 mins ppm

176 13 C MAS NMR spectrum of H-ZSM-5 with 50 torr of adsorbed MeOH heated to 300 °C for 35 mins ppm scalar coupling 1 J CH = 125 Hz a quintet with ratio 1:4:6:4:1 is expected for methane

177 Heteronuclear 2D J-resolved 13 C MAS NMR spectrum ppm Hz

178 13 C NMR spin diffusion spectrum of products of methanol conversion over zeolite ZSM ppm

179 13 C MAS NMR spectrum of H-ZSM-5 with 50 torr of adsorbed MeOH heated to 300 °C for 35 mins ppm Methane Ethane Propane Cyclopropane n-Butane Isobutane (n-Pentane) Isopentane n-Hexane n-Heptane

180 Methylated aromatic products ppm CO * *** *

181 129 Xe NMR as a sensitive tool for materials 0:reference S:surface collisions Xe:Xe-Xe collisions E:electric field effect M:paramagnetic species

182 129 Xe as a sensitive probe for various zeolites Xe atoms /g ppm omega NaY ZK4 K - L ZSM-11 ZSM-5

183 Applications Polymers Glasses Porous materials Liquid crystals

184 Graphitic nanowires Hexa-peri-hexabenzocoronene (HBC)

185 HBC monolayer on HOPG

186 Phase transitions of alkyl substituted HBC

187 Temperature dependence of the one dimensional charge carrier mobility

188 Liquid crystalline (dichotic) behaviour of alkyl substituted HBC‘s R = C 12 H 25 Hexadodecyl-hexa-peri-hexabenzocoronene (HBC-C 12 )

189 Charge carrier mobility in HHTT

190 1 H DQ MAS NMR spectra of HBC-C 12  -deuteratedfully protonated

191

192 Proposed stacking model based on solid state NMR

193 „Graphitic“ stacking

194 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: with Ref.: Graf et al. J. Chem. Phys. 1997, 106, 885  and  are Euler angles relating the PAF of the diploar coupling tensor to the rotor fixed reference frame -> distance information in a rigid system, or indication of mobility:

195 Homonuclear correlation between I = 1 / 2 spins

196 aromatic protons at 8.3 ppm (crystalline phase) aromatic protons at 6.2 ppm (LC phase) aliphatic protons at 1.2 ppm (crystalline phase) fitted dipolar coupling constants DQ spinning side band patterns  R = 35 kHz  R = 10 kHz  R = 35 kHz

197 Effect of additional phenyl spacers R = -C 12 H 25 or -C 6 H 4 -C 12 H 25

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200 Space filling model for HBC-PhC 1

201 X-ray diffraction patterns of the mesophases

202 Let us have a tour of solid state NMR following Professor Malcolm H. Levitt.

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