Electrochemical Oxidative Fluorination of an Oxide Perovskite

<div>We report the successful electrochemical intercalation of F-ions into a densely packed perovskite oxide from a liquid electrolyte at room temperature. Using galvanostatic oxidation and electrochemical impedance spectroscopy coupled with operando X-ray diffraction, we show that roughly 0.5 equivalents of F-ions can be inserted onto the vacant A-site of the perovskite ReO3. Density functional theory calculations indicate that the intercalated phase is thermodynamically unfavorable compared to other less densely packed polymorphs of ReO3F. Pairing X-ray spectroscopy, neutron total scattering measurements, and magic-angle spinning 19F NMR confirms a rapid decomposition of the product on removal from the cell but nevertheless, these results clearly demonstrate that small anions like fluoride can be intercalated into solids as readily as alkali cations at room temperature, which opens new opportunities to electrochemically fluorinate many new materials.</div>

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19F Magic Angle Spinning NMR Spectroscopy and Density Functional Theory Calculations of Fluorosubstituted Tryptophans: Integrating Experiment and Theory for Accurate Determination of Chemical Shift Tensors

The Journal of Physical Chemistry B ◽

10.1021/acs.jpcb.8b00377 ◽

2018 ◽

Vol 122 (23) ◽

pp. 6148-6155 ◽

Cited By ~ 11

Author(s):

Manman Lu ◽

Sucharita Sarkar ◽

Mingzhang Wang ◽

Jodi Kraus ◽

Matthew Fritz ◽

...

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Accurate Determination ◽

Density Functional Theory Calculations ◽

Magic Angle Spinning ◽

Magic Angle ◽

Functional Theory ◽

Chemical Shift Tensors ◽

Angle Spinning

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The crystal chemistry of rhodizite: a re-examination

Mineralogical Magazine ◽

10.1180/minmag.1986.050.355.22 ◽

1986 ◽

Vol 50 (355) ◽

pp. 163-172 ◽

Cited By ~ 15

Author(s):

A. Pring ◽

V. K. Din ◽

D. A. Jefferson ◽

J. M. Thomas

Keyword(s):

Single Crystal ◽

Crystal Chemistry ◽

Structure Refinement ◽

High Resolution Electron Microscopy ◽

Basic Structure ◽

Magic Angle Spinning ◽

Magic Angle ◽

Alkali Cations ◽

X Ray ◽

Using Data

AbstractThe crystal chemistry of rhodizite was re-examined using data from high-resolution electron microscopy (HREM), magic angle spinning nuclear magnetic resonance (MASNMR), a single crystal X-ray structure refinement, and a new chemical analysis. The analysis calculates to the formula: (K0.46Cs0.36Rb0.06 Na0.02)Σ0.90Al3.99Be4(B11·35Be0.55Li0.02)O28· The distribution of alkali cations was shown to be truly random by HREM images and computer image simulations. The distribution of boron and beryllium was monitored by MASNMR, the spectra for both elements gave only single resonances indicating that all beryllium and boron atoms are located in chemically equivalent sites. The structure of rhodizite was refined by single crystal X-ray diffraction techniques. The mineral is cubic a = 7.318(1) Å, space group P3. A full matrix least-squares refinement using 152 unique observed reflections [F > 3σ(F)] converged to R = 0.0344. The refinement confirmed the basic structure as determined by Taxer and Buerger (1967), 4 beryllium atoms of the unit cell were found to occupy a 4e special position, the remaining 0.5 being randomly distributed with the 11.35 boron atoms over the 12h sites.

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High-Pressure Structural Behavior and Equation of State of Kagome Staircase Compound, Ni3V2O8

Crystals ◽

10.3390/cryst10100910 ◽

2020 ◽

Vol 10 (10) ◽

pp. 910

Author(s):

Daniel Diaz-Anichtchenko ◽

Robin Turnbull ◽

Enrico Bandiello ◽

Simone Anzellini ◽

Daniel Errandonea

Keyword(s):

High Pressure ◽

Equation Of State ◽

Density Functional ◽

Room Temperature ◽

Ambient Pressure ◽

Density Functional Theory Calculations ◽

X Ray Diffraction ◽

X Ray ◽

Cell Parameters ◽

A Chain

We report on high-pressure synchrotron X-ray diffraction measurements on Ni3V2O8 at room-temperature up to 23 GPa. According to this study, the ambient-pressure orthorhombic structure remains stable up to the highest pressure reached in the experiments. We have also obtained the pressure dependence of the unit-cell parameters, which reveals an anisotropic compression behavior. In addition, a room-temperature pressure–volume third-order Birch–Murnaghan equation of state has been obtained with parameters: V0 = 555.7(2) Å3, K0 = 139(3) GPa, and K0′ = 4.4(3). According to this result, Ni3V2O8 is the least compressible kagome-type vanadate. The changes of the crystal structure under compression have been related to the presence of a chain of edge-sharing NiO6 octahedral units forming kagome staircases interconnected by VO4 rigid tetrahedral units. The reported results are discussed in comparison with high-pressure X-ray diffraction results from isostructural Zn3V2O8 and density-functional theory calculations on several isostructural vanadates.

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Insight into the Crystalline Structure of ThF4 with the Combined Use of Neutron Diffraction, 19F Magic-Angle Spinning-NMR, and Density Functional Theory Calculations

Inorganic Chemistry ◽

10.1021/acs.inorgchem.8b02683 ◽

2018 ◽

Vol 57 (24) ◽

pp. 15350-15360 ◽

Cited By ~ 2

Author(s):

Laura Martel ◽

Elisa Capelli ◽

Monique Body ◽

Marco Klipfel ◽

Ondrej Beneš ◽

...

Keyword(s):

Density Functional Theory ◽

Neutron Diffraction ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Magic Angle Spinning ◽

Magic Angle ◽

Functional Theory ◽

Combined Use ◽

Angle Spinning ◽

Insight Into

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13C and 19F solid-state NMR and X-ray crystallographic study of halogen-bonded frameworks featuring nitrogen-containing heterocycles

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229616015023 ◽

2017 ◽

Vol 73 (3) ◽

pp. 157-167 ◽

Cited By ~ 24

Author(s):

Patrick M. J. Szell ◽

Shaina A. Gabriel ◽

Russell D. D. Gill ◽

Shirley Y. H. Wan ◽

Bulat Gabidullin ◽

...

Keyword(s):

Solid State ◽

Density Functional ◽

Halogen Bond ◽

Chemical Shifts ◽

Halogen Bonding ◽

Structural Features ◽

Magic Angle Spinning ◽

Magic Angle ◽

X Ray ◽

Donor And Acceptor

Halogen bonding is a noncovalent interaction between the electrophilic region of a halogen (σ-hole) and an electron donor. We report a crystallographic and structural analysis of halogen-bonded compounds by applying a combined X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (SSNMR) approach. Single-crystal XRD was first used to characterize the halogen-bonded cocrystals formed between two fluorinated halogen-bond donors (1,4-diiodotetrafluorobenzene and 1,3,5-trifluoro-2,4,6-triiodobenzene) and several nitrogen-containing heterocycles (acridine, 1,10-phenanthroline, 2,3,5,6-tetramethylpyrazine, and hexamethylenetetramine). New structures are reported for the following three cocrystals, all in the P21/c space group: acridine–1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C6F3I3·C13H9N, 1,10-phenanthroline–1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C6F3I3·C12H8N2, and 2,3,5,6-tetramethylpyrazine–1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), C6F3I3·C8H12N2. 13C and 19F solid-state magic-angle spinning (MAS) NMR is shown to be a convenient method to characterize the structural features of the halogen-bond donor and acceptor, with chemical shifts attributable to cocrystal formation observed in the spectra of both nuclides. Cross polarization (CP) from 19F to 13C results in improved spectral sensitivity in characterizing the perfluorinated halogen-bond donor when compared to conventional 1H CP. Gauge-including projector-augmented wave density functional theory (GIPAW DFT) calculations of magnetic shielding constants, along with optimization of the XRD structures, provide a final set of structures in best agreement with the experimental 13C and 19F chemical shifts. Data for carbons bonded to iodine remain outliers due to well-known relativistic effects.

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Local Structure of Cationic Sites in Dehydrated Zeolites Inferred from 27Al Magic-Angle Spinning NMR and Density Functional Theory Calculations. A Study on Li-, Na-, and K-Chabazite

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.6b04391 ◽

2016 ◽

Vol 120 (26) ◽

pp. 14216-14225 ◽

Cited By ~ 10

Author(s):

Petr Klein ◽

Veronika Pashkova ◽

Haunani M. Thomas ◽

Sarah R. Whittleton ◽

Jiri Brus ◽

...

Keyword(s):

Density Functional Theory ◽

Local Structure ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Magic Angle Spinning ◽

Magic Angle ◽

Functional Theory ◽

Angle Spinning

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Structural, Thermal, and Vibrational Properties of N,N-Dimethylglycine–Chloranilic Acid—A New Co-Crystal Based on an Aliphatic Amino Acid

Materials ◽

10.3390/ma14123292 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3292

Author(s):

Joanna Hetmańczyk ◽

Łukasz Hetmańczyk ◽

Joanna Nowicka-Scheibe ◽

Andrzej Pawlukojć ◽

Jan K. Maurin ◽

...

Keyword(s):

Density Functional ◽

Magic Angle Spinning ◽

Vibrational Properties ◽

Magic Angle ◽

X Ray Diffraction ◽

Deprotonated Form ◽

Aliphatic Amino Acid ◽

Chloranilic Acid ◽

Bending Vibration ◽

X Ray

The new complex of N,N-Dimethylglycine (DMG) with chloranilic acid (CLA) was synthesized and examined for thermal, structural, and dynamical properties. The structure of the reaction product between DMG and CLA was investigated in a deuterated dimethyl sulfoxide (DMSO-d6) solution and in the solid state by Nuclear Magnetic Resonance (NMR) (Cross Polarization Magic Angle Spinning-CPMAS NMR). The formation of the 1:1 complex of CLA and DMG in the DMSO solution was also confirmed by diffusion measurement. X-ray single crystal diffraction results revealed that the N,N-dimethylglycine–chloranilic acid (DMG+–CLA−) complex crystallizes in the centrosymmetric triclinic P-1 space group. The X-ray diffraction and NMR spectroscopy show the presence of the protonated form of N,N-dimethylglycine and the deprotonated form of chloranilic acid molecules. The vibrational properties of the co-crystal were investigated by the use of neutron (INS), infrared (IR), and Raman (RS) spectroscopies, as well as the density functional theory (DFT) with periodic boundary conditions. From the band shape analysis of the N–CH3 bending vibration, we can conclude that the CH3 groups perform fast (τR ≈ 10−11 to 10‒13 s) reorientational motions down to a temperature of 140 K, with activation energy at ca. 6.7 kJmol–1. X-ray diffraction and IR investigations confirm the presence of a strong N+–H···O− hydrogen bond in the studied co-crystal.

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Intercalation of Si between MoS2 layers

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.8.196 ◽

2017 ◽

Vol 8 ◽

pp. 1952-1960 ◽

Cited By ~ 13

Author(s):

Rik van Bremen ◽

Qirong Yao ◽

Soumya Banerjee ◽

Deniz Cakir ◽

Nuri Oncel ◽

...

Keyword(s):

Lattice Constant ◽

Density Functional ◽

Room Temperature ◽

Density Functional Theory Calculations ◽

Scanning Tunneling Spectroscopy ◽

Scanning Tunneling ◽

Functional Theory ◽

X Ray ◽

Highly Strained ◽

The Hill

We report a combined experimental and theoretical study of the growth of sub-monolayer amounts of silicon (Si) on molybdenum disulfide (MoS2). At room temperature and low deposition rates we have found compelling evidence that the deposited Si atoms intercalate between the MoS2 layers. Our evidence relies on several experimental observations: (1) Upon the deposition of Si on pristine MoS2 the morphology of the surface transforms from a smooth surface to a hill-and-valley surface. The lattice constant of the hill-and-valley structure amounts to 3.16 Å, which is exactly the lattice constant of pristine MoS2. (2) The transitions from hills to valleys are not abrupt, as one would expect for epitaxial islands growing on-top of a substrate, but very gradual. (3) I(V) scanning tunneling spectroscopy spectra recorded at the hills and valleys reveal no noteworthy differences. (4) Spatial maps of dI/dz reveal that the surface exhibits a uniform work function and a lattice constant of 3.16 Å. (5) X-ray photo-electron spectroscopy measurements reveal that sputtering of the MoS2/Si substrate does not lead to a decrease, but an increase of the relative Si signal. Based on these experimental observations we have to conclude that deposited Si atoms do not reside on the MoS2 surface, but rather intercalate between the MoS2 layers. Our conclusion that Si intercalates upon the deposition on MoS2 is at variance with the interpretation by Chiappe et al. (Adv. Mater. 2014, 26, 2096–2101) that silicon forms a highly strained epitaxial layer on MoS2. Finally, density functional theory calculations indicate that silicene clusters encapsulated by MoS2 are stable.

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