Publications de David Lyndon Emsley

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A prerequisite for NMR studies of organic materials is assigning each experimental chemical shift to a set of geometrically equivalent nuclei. Obtaining the assignment experimentally can be challenging and typically requires time-consuming multidimensional ...

Nowadays, drug encapsulation and drug release from cellulose nanofibrils systems are intense research topics, and commercial grades of cellulose nanomaterials are currently available. In this work we present an ester-containing prodrug of metronidazole tha ...

Lanthanides are versatile modulators of optoelectronic properties owing to their narrow optical emission spectra across the visible and near-infrared range. Their use in metal halide perovskites (MHPs) has recently gained prominence, although their fate in ...

We investigate the presence of a surface species for the active pharmaceutical ingredient (API) AZD9496 with dynamic nuclear polarization surface enhanced nuclear spectroscopy (DNP SENS). We show that using DNP we can elucidate the presence of an amorphous ...

Nuclear Magnetic Resonance (NMR) chemical shifts are powerful probes of local atomic and electronic structure that can be used to resolve the structures of powdered or amorphous molecular solids. Chemical shift driven structure elucidation depends critical ...

Dynamic Nuclear Polarization MAS NMR is introduced to characterize model methylcellulose ether compounds at natural isotopic abundance. In particular an approach is provided to determine the position of the methyl ether group within the repeating unit. Spe ...

Protein-based drugs are becoming increasingly important, but there are challenges associated with their formulation (for example, formulating stable inhalable aerosols while maintaining the proper long-term stability of the protein). Determining the morpho ...

We report on the preparation of MAPbBr(3) perovskite films of high electronic quality by applying a methylamine (MA) vapor treatment and mitigating surface defects using the amphiphilic molecular passivator, neopentylammonium chloride (NPACl). We find that ...

We show how dynamic nuclear polarization (DNP) enhanced solid-state NMR spectroscopy can be used to characterize polymorphs and solvates of organic solids. We applied DNP to three polymorphs and one hydrated form of the asthma drug molecule theophylline. F ...

The surface of gamma-alumina nanoparticles can be characterized by dynamic nuclear polarization (DNP) surface-enhanced NMR of Al-27. DNP is combined with cross-polarization and MQ-MAS to determine local symmetries of Al-27 sites at the surface. ...

Low-dimensional hybrid perovskites have emerged as promising materials for optoelectronic applications. Although these materials have already demonstrated enhanced stability as compared to their three-dimensional perovskite analogues, their functionality h ...

Photoinduced halide segregation hinders widespread application of three-dimensional (3D) mixed-halide perovskites. Much less is known about this phenomenon in lower-dimensional systems. Here, we study photoinduced halide segregation in lower-dimensional mi ...

Halide perovskites are promising next-generation solar cell materials, but their commercialization is hampered by their propensity to degrade under operating conditions, particularly under heat, humidity, and light. Identifying degradation products and lin ...

Due to their strong dependence on local atonic environments, NMR chemical shifts are among the most powerful tools for strucutre elucidation of powdered solids or amorphous materials. Unfortunately, using them for structure determination depends on the abi ...

One key bottleneck of solid-state NMR spectroscopy is that H-1 NMR spectra of organic solids are often very broad due to the presence of a strong network of dipolar couplings. We have recently suggested a new approach to tackle this problem. More specifica ...

We review our recent paper which resolves the long-standing dilemma of the location and nature of the six-fold coordinated aluminum in calcium aluminate silicate hydrate (C-A-S-H) samples. First principles calculations predict that at high Ca:Si and H2O ra ...

In 1H MAS spectra, the residual homogeneous broadening under MAS is due to a combination of higher-order shifts and splittings. We have recently shown how the two-dimensional anti-z-COSY experiment can be used for the removal of the splittings. However, th ...

A new 3.2 mm 1H–19F–X magic angle spinning dynamic nuclear polarization NMR (MAS DNP-NMR) probe was developed with a unique coil design with separate radiofrequency channels for 1H excitation and 13C or 19F detection to enable acquisition of 1H–19F cross-p ...

The sensitivity of NMR spectroscopy is considerably enhanced by dynamic nuclear polarization (DNP). In DNP polarization is transferred from unpaired electrons of a polarizing agent to nearby proton spins. In solids, this transfer is followed by the transpo ...

All-inorganic perovskite films hold promise for improving the stability of perovskite solar cells (PSCs). However, the 3D alpha phase of narrow-bandgap inorganic perovskites is thermodynamically unstable at room temperature, limiting the development of hig ...

David Lyndon Emsley

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Bayesian probabilistic assignment of chemical shifts in organic solids

Two-step immobilization of metronidazole prodrug on TEMPO cellulose nanofibrils through thiol-yne click chemistry for in situ controlled release

Speciation of Lanthanide Metal Ion Dopants in Microcrystalline All-Inorganic Halide Perovskite CsPbCl3

High Sensitivity Detection of a Solubility Limiting Surface Transformation of Drug Particles by DNP SENS

A Deep Learning Model for Chemical Shieldings in Molecular Organic Solids Including Anisotropy

Advanced characterization of regioselectively substituted methylcellulose model compounds by DNP enhanced solid-state NMR spectroscopy

Hierarchy of the Components in Spray-Dried, Protein-Excipient Particles Using DNP-Enhanced NMR Spectroscopy

Efficient and Stable Large Bandgap MAPbBr(3) Perovskite Solar Cell Attaining an Open Circuit Voltage of 1.65 V

Polymorphs of Theophylline Characterized by DNP Enhanced Solid-State NMR

Dynamic nuclear polarization of quadrupolar nuclei using cross polarization from protons: surface-enhanced aluminium-27 NMR

Naphthalenediimide/Formamidinium-Based Low-Dimensional Perovskites

Light-Induced Halide Segregation in 2D and Quasi-2D Mixed-Halide Perovskites

Light-Induced Metallic and Paramagnetic Defects in Halide Perovskites from Magnetic Resonance

Chemical shifts in molecular solids by machine learning

Two-dimensional Pure Isotropic Proton Solid State NMR

The Atomic-Level Structure of Cementitious Calcium Aluminate Silicate Hydrate Determined by NMR

Fast remote correlation experiments for 1H homonuclear decoupling in solids

1H–19F cross-polarization magic angle spinning dynamic nuclear polarization NMR investigation of advanced pharmaceutical formulations

Deuterated TEKPol Biradicals and the Spin-Diffusion Barrier in MAS DNP

Europium-Doped CsPbI2Br for Stable and Highly Efficient Inorganic Perovskite Solar Cells