last week in chemistry

103

new preprints about chemistry in the last week

chemRxiv

most active server in chemistry in the last week

transition metal

7 preprints

Computational Screening of Transition Metal /p-block Hybrid Electrocatalysts for CO2 Reduction

We developed thermodynamic volcano plots with two descriptors; CO* and OH* binding free energies and determined the best catalyst material among the initially investigated catalyst materials expecting this plot will provide guidance to the future work on improving the activity of transition metal-p block catalysts for...
4 days ago
chemRxiv

Heterolytic Hydrogen Activation: Understanding Support Effects in Water-Gas Shift, Hydrodeoxygenation, and CO Oxidation Catalysis

The dissimilar equilibrium constant, or oxophilicity, between early and late transition metals exemplify the utility of metal-support interfacial sites to circumvent adsorption-energy scaling restrictions, thereby providing bifunctional gains for the WGS reaction class.
30 hours ago
chemRxiv

The Dynamic Ligand Field of a Molecular Qubit: Decoherence Through Spin–Phonon Coupling

Here we derive a general ligand field theory model to describe and quantify the nature of spin–phonon coupling terms in S = 1/2 transition metal complexes.
5 days ago
chemRxiv

functional theory

7 preprints

Identifying the Molecular Edge Termination of Exfoliated Hexagonal Boron Nitride Nanosheets with Solid-State NMR Spectroscopy and Plane-Wave DFT Calculations

Here, high-resolution magic-angle spinning (MAS) solid-state NMR (SSNMR) spectroscopy and plane-wave density-functional theory (DFT) calculations are used to determine the exact molecular edge termination in exfoliated h-BNNS. 1H→11B cross-polarization MAS (CPMAS) SSNMR spectra of h-BNNS revealed multiple hydroxyl/oxygen...
30 hours ago
chemRxiv

Benchmarking Electronic Structure Methods for Accurate Fixed-Charge Electrostatic Models

We further demonstrate that using computationally inexpensive density functional theory (DFT) methods, together with appropriate augmented basis sets and a continuum solvent model, can yield molecular dipole moments that are both more strongly and more uniformly overpolarized.
5 days ago
chemRxiv

Theoretical Examination of Efficiency of Anthocyanidins as Sensitizers in Dye-Sensitized Solar Cells

In this study structural effects and electronic contributions of four anthocyanidins, cyanidin (Cy), delphinidin (Dp), malvidin (Mv) and pelargonidin (Pg), to improve the efficiency of DSSCs were investigated, using quantum chemical method, the density functional theory (DFT), to calculate parameters such as frontier...
5 days ago
chemRxiv

c h

6 preprints

Photocontrolled Radical Polymerization from Hydridic C–H Bonds

Finally, we demonstrate that we can graft polymer chains controllably from poly(ethylene glycol) showcasing the potential application of this method for controlled grafting from C–H bonds of commodity polymers.
5 days ago
chemRxiv

Mechanism of the Arene-Limited Nondirected CH Activation of Arenes with Palladium: A Combined Experimental and Theoretical Study

These findings are expected to be highly useful for further method development using this powerful class of catalysts.
3 days ago
chemRxiv

Direct CH Alpha Arylation of Enones with ArI(O2CR)2 Reagents

Mechanistic investigations implicate arylation via an umpoled “enolonium” species and that the presence of a b-pyridinium moiety is critical for desired C–C bond formation.
3 days ago
chemRxiv

molecular dynamics

6 preprints

Comment on 'Response to comment on \'Valid molecular dynamics simulations of human hemoglobin require a surprisingly large box size\'\'

We recently expressed three major concerns about a 2018 article of El Hage et al. about a claimed effect of the box size in molecular dynamics simulations of hemoglobin.
29 hours ago
bioRxiv

Fragment Pose Prediction Using Non-Equilibrium Candidate Monte Carlo and Molecular Dynamics Simulations

In this retrospective study, we compare how computational approaches like docking, molecular dynamics (MD) simulations, and a non-equilibrium candidate Monte Carlo (NCMC) based method (NCMC+MD) perform in predicting binding modes for a set of 12 fragment-like molecules which bind to soluble epoxide hydrolase.
30 hours ago
chemRxiv

Alchemical Hydration Free Energy Calculations Using Molecular Dynamics with Explicit Polarization and Induced Polarity Decoupling: An OTFP Approach

We present an algorithm to calculate hydration free energies in explicit solvent that incorporates polarization of the solute molecule in conjunction with the use of a classical fixed--charge force field.
30 hours ago
chemRxiv

high throughput

5 preprints

High-throughput, temporal and dose dependent, effect of vitamins and minerals on chondrogenesis

This high-throughput platform was used to assess the effect of vitamins and minerals, alone and in combination with TGF{beta}1, on type II collagen expression.
5 days ago
bioRxiv

Bayesian modelling of high-throughput sequencing assays with malacoda

High-throughput screens powered by NGS have greatly increased the rate of variant functionalization, but the development of comprehensive statistical methods to analyze screen data has lagged behind.
1 day ago
bioRxiv

Third-Generation Method for High Throughput Quantification of Trace Palladium by Color or Fluorescence

We previously reported a colorimetric method for trace palladium quantification, the only high throughput method implemented in the pharmaceutical industry.
30 hours ago
chemRxiv

dft calculations

5 preprints

Identifying the Molecular Edge Termination of Exfoliated Hexagonal Boron Nitride Nanosheets with Solid-State NMR Spectroscopy and Plane-Wave DFT Calculations

Plane-wave DFT calculations were used to construct model edge structures and predict the corresponding 11B, 14N and 15N SSNMR spectra.
30 hours ago
chemRxiv

In-Situ Formation of H-Bonding Imidazole Chains in Break-Junction Experiments

The results are supported by DFT calculations, which confirmed our hypothesis.
5 days ago
chemRxiv

Terbium(III) Phthalocyaninato Multiple-Decker Complexes in High Oxidation States: Correlation Between Electronic, Structural and Magnetic Properties and Unexpected Triplet Biradical States

The X-ray structural analysis for the series of oxidized multiple-decker complexes revealed that all the species show an axial compression induced by the ligand oxidations, resulting in the bowl-shaped distortion of the ligands, in agreement with predictions from DFT calculations.
4 days ago
chemRxiv

reaction conditions

5 preprints

Third-Generation Method for High Throughput Quantification of Trace Palladium by Color or Fluorescence

We changed the reaction conditions and procedure accordingly, which substantially improved reproducibility.
30 hours ago
chemRxiv

Lysine Acylation Using Conjugating Enzymes (LACE) for Site-Specific Modification and Ubiquitination of Native Proteins

Enzymes are powerful tools for post-translational protein labeling due to their high sequence specificity and mild reaction conditions.
1 day ago
chemRxiv

Chiral Tetrahydropyridines via FeCl3-Catalyzed Carbonyl-Olefin Metathesis

This strategy relies on FeCl3 as an inexpensive and environmentally benign catalyst and enables access to a variety of substituted tetrahydropyridines under mild reaction conditions.
3 days ago
chemRxiv

solid state

4 preprints

Identifying the Molecular Edge Termination of Exfoliated Hexagonal Boron Nitride Nanosheets with Solid-State NMR Spectroscopy and Plane-Wave DFT Calculations

Here, high-resolution magic-angle spinning (MAS) solid-state NMR (SSNMR) spectroscopy and plane-wave density-functional theory (DFT) calculations are used to determine the exact molecular edge termination in exfoliated h-BNNS. 1H→11B cross-polarization MAS (CPMAS) SSNMR spectra of h-BNNS revealed multiple hydroxyl/oxygen...
30 hours ago
chemRxiv

Rational Design of Quasi Zero-Strain NCM Cathode Materials for Minimizing Volume Change Effects in All-Solid-State Batteries

Measures to improve the cycling performance and stability of bulk-type all-solid-state batteries (SSBs) are currently being developed with the goal of substituting conventional Li-ion battery (LIB) technology.
4 days ago
chemRxiv

Fundamental Design Rules for Turning on Fluorescence in Ionic Molecular Crystals

While molecular fluorophores that show bright emission in solution are potential sources of these materials, their emission is frequently lost in the solid state preventing their direct translation to optical applications.
4 days ago
chemRxiv

machine learning

4 preprints

Distinguishing between paediatric brain tumour types using multi-parametric magnetic resonance imaging and machine learning: a multi-site study

The results show that diffusion and perfusion weighted imaging of both the tumour and whole brain provide significant features which differ between tumour types, and that combining these features gives the optimal machine learning classifier with greater than 80 percent predictive precision.
5 days ago
arXiv

Machine Learning for Inferring CO2 Fluxes: The New Metaphysics of Neural Nets

A non-intuitive machine learning metaphysical result was observed by the omission of CO2 concentrations as an input variable.
2 days ago
EarthArXiv

Multi-omics-based pan-cancer prognosis prediction using an ensemble of deep-learning and machine-learning models

We introduce DeepProg, a new computational framework that robustly predicts patient survival subtypes based on multiple types of omic data, using an ensemble of deep-learning and machine-learning models.
1 day ago
medRxiv

small molecules

4 preprints

Manumycin Polyketides Act as Molecular Glues Between UBR7 and P53 to Impair Breast Cancer Pathogenicity

Molecular glues are an intriguing therapeutic modality that harness small-molecules to induce interactions between proteins that typically do not interact, thus enabling the creation of novel protein functions not naturally encoded in biology.
4 days ago
bioRxiv

Fragment Pose Prediction Using Non-Equilibrium Candidate Monte Carlo and Molecular Dynamics Simulations

Our findings suggest that even with small fragment-like molecules, we fail to sample all the crystallographic binding modes using microsecond MD simulations, but using NCMC+MD we have better success in sampling the crystal structure while obtaining the correct populations.
30 hours ago
chemRxiv

Targeting the PI5P4K lipid kinase family in cancer using novel covalent inhibitors

However, the therapeutic potential of targeting these kinases is understudied due to a lack of potent, specific small molecules available.
27 hours ago
bioRxiv

long standing

4 preprints

Mechanism of the Arene-Limited Nondirected C–H Activation of Arenes with Palladium: A Combined Experimental and Theoretical Study

By overcoming this long standing challenge, such methods have now become suitable for the functionalization of complex organic molecules.
3 days ago
chemRxiv

A General Carbonyl Alkylative Amination Process for Tertiary Amine Synthesis

We report a practical and general solution to this long-standing synthetic challenge can be accomplished by addition of alkyl radicals to all alkyl-iminium ions.
1 day ago
chemRxiv

Fundamental Design Rules for Turning on Fluorescence in Ionic Molecular Crystals

We report the serendipitous discovery of a new type of material that we call small-molecule ionic isolation lattices(SMILES) tackling this long-standing problem.
4 days ago
chemRxiv

class of materials

3 preprints

A Pyridinic Fe-N4 Macrocycle Effectively Models the Active Sites in Fe/N-Doped Carbon Electrocatalysts

A leading postulate is that iron active sites in this class of materials exist in an Fe-N4 pyridinic ligation environment.
3 days ago
chemRxiv

Robot-Accelerated Perovskite Investigation and Discovery (RAPID): 1. Inverse Temperature Crystallization

Metal halide perovskites are a promising class of materials for next-generation photovoltaic and optoelectronic devices.
2 days ago
chemRxiv

Exploring the Dynamics of Bound Water in Nylon Polymers with Terahertz Spectroscopy

These results highlight the significant utility of using THz spectroscopy to study the hydration dynamics and spectral signature of bound water in this important class of materials.
3 days ago
chemRxiv

molecular structure

3 preprints

Visualizing 3D Molecular Structures Using an Augmented Reality App

The method works for all molecules including small molecules, supramolecular structures, MOFs and biomacromolecules.
30 hours ago
chemRxiv

Electrostatics, Hydrogen Bonding, and Molecular Structure at Polycation and Peptide:Lipid Membrane Interfaces

This finding could be essential for understanding the underlying first steps of cell lysis and penetration by polycations and should be explored further.
2 days ago
chemRxiv

Size-Extensive Molecular Machine Learning with Global Descriptors

Such ML models require descriptors that encode the molecular structure in a vector.
4 days ago
chemRxiv

non equilibrium

3 preprints

Fragment Pose Prediction Using Non-Equilibrium Candidate Monte Carlo and Molecular Dynamics Simulations

In this retrospective study, we compare how computational approaches like docking, molecular dynamics (MD) simulations, and a non-equilibrium candidate Monte Carlo (NCMC) based method (NCMC+MD) perform in predicting binding modes for a set of 12 fragment-like molecules which bind to soluble epoxide hydrolase.
30 hours ago
chemRxiv

Re-Programming Hydrogel Properties using a Fuel-driven Reaction Cycle

Overall, we show how catalysis can control fuel generation to control reaction / assembly kinetics and materials properties in life-like non-equilibrium systems.
5 days ago
chemRxiv

Thermal versus Mechanical Unfolding in a Model Protein

When unfolded by non-equilibrium force extension and constant force protocols, we recover a simple two barrier landscape, as the protein reaches the extended conformation through a metastable intermediate.
3 days ago
bioRxiv

hydrogen bonding

3 preprints

In-Situ Formation of H-Bonding Imidazole Chains in Break-Junction Experiments

These findings pave the road to the use of hydrogen-bonding networks for the fabrication of dynamic junctions based on supramolecular interactions.
5 days ago
chemRxiv

Electrostatics, Hydrogen Bonding, and Molecular Structure at Polycation and Peptide:Lipid Membrane Interfaces

This finding could be essential for understanding the underlying first steps of cell lysis and penetration by polycations and should be explored further.
2 days ago
chemRxiv

Origins of Negative and Positive Electromechanical Response of Oligopeptide Piezoelectrics

While the overall molecular dipole moment may favor positive piezoresponse, individual hydrogen bonding interactions along the backbone have the opposite direction, enabling tailored sequences to yield either net expansion or contraction in response to an electric field.
5 days ago
chemRxiv

h bond

3 preprints

Photocontrolled Radical Polymerization from Hydridic C–H Bonds

Finally, we demonstrate that we can graft polymer chains controllably from poly(ethylene glycol) showcasing the potential application of this method for controlled grafting from C–H bonds of commodity polymers.
5 days ago
chemRxiv

In-Situ Formation of H-Bonding Imidazole Chains in Break-Junction Experiments

These findings pave the road to the use of hydrogen-bonding networks for the fabrication of dynamic junctions based on supramolecular interactions.
5 days ago
chemRxiv

Formation of Enamines via Catalytic Dehydrogenation by Pincer-Iridium Complexes

Experimentally determined kinetic isotope effects in conjunction with DFT-based analysis support a dehydrogenation mechanism involving initial pre-equilibrium oxidative addition of the amine α C-H bond followed by rate-determining elimination of the β-C-H bond.
3 days ago
chemRxiv

molecular level

3 preprints

A Molecular-Level Mechanism of the Biological N2 Fixation

We present a detailed molecular-level mechanism for the biological fixation of atmospheric nitrogen into ammonia.
30 hours ago
chemRxiv

Real-Time Video Imaging of Mechanical Motions of a Single Molecular Shuttle

We have realized high spatial precision of distance measurement with the standard error of the mean as small as ± 0.01 nm, and revealed the rich molecular dynamics, where motions are non-linear, stochastic and often non-repeatable, and a work and energy relationship at a molecular level previously undetected by time-averaged...
30 hours ago
chemRxiv

Interaction between myricetin aggregates and lipase under simplified intestinal conditions

Although lipase inhibition by myricetin at a molecular level has been reported previously, the results of this study suggest that myricetin aggregates inhibit lipase by a sequestering mechanism as well.
4 days ago
bioRxiv

uv vis

3 preprints

Persistent Radical Pairs Between N-Substituted Naphthalimide and Carbanion Exhibit pKa-Dependent UV-vis Absorption

A new strategy is constructed for estimating and screening pKa values among different carbon acids under ambient conditions via the UV-vis absorption spectrum of persistent radical pair originating from an N-substituted naphthalimide (NNI) derivative in the presence of various carbanions in organic solutions
3 days ago
chemRxiv

Structure-Property Relationships in Unsymmetric Bis(antiaromatics): Who Wins the Battle Between Pentalene and Benzocyclobutadiene?

The antiaromatic character of the molecules are supported experimentally by 1H NMR, UV-Vis and cyclic voltammetry measurements and X-ray crystallography.
5 days ago
chemRxiv

Plasmonic Oligomers With Tunable Conductive Nanojunctions

We follow the oligomer formation and the deposition of the second metal (i.e. silver or palladium) via UV/Vis spectroscopy and we map the plasmonic properties of the nanostructures at nanometer scale using electron energy loss spectroscopy.
3 days ago
chemRxiv

electronic structure

3 preprints

Benchmarking Electronic Structure Methods for Accurate Fixed-Charge Electrostatic Models

Some popular fixed-charge MM force fields use partial atomic charges derived from gas phase electronic structure calculations using the Hartree-Fock method with the relatively small 6-31G* basis set (HF/6-31G*).
5 days ago
chemRxiv

Terbium(III) Phthalocyaninato Multiple-Decker Complexes in High Oxidation States: Correlation Between Electronic, Structural and Magnetic Properties and Unexpected Triplet Biradical States

Magnetic measurements revealed that the series of complexes show single-molecule magnet (SMM) properties, which are controlled by the multi-step redox induced structural changes.
4 days ago
chemRxiv

Size-Extensive Molecular Machine Learning with Global Descriptors

Machine learning (ML) models are increasingly used to predict molecular prop- erties in a high-throughput setting at a much lower computational cost than con- ventional electronic structure calculations.
4 days ago
chemRxiv

fluorescent whitening

2 preprints

A Study on the Removal of Fluorescent Whitening Agent by Pretreatment Ozone Oxidation for MBR Process Application

The removal efficiencies of fluorescent whitening agents, a diaminostilbene disulfonic acid derivative by ozone oxidation were evaluated by UV254 Scan, COD, T-N and color using a synthetic wastewater sample (COD=433.0 mg/ℓ) and paper and paper mill wastewater (COD=157.2 mg/ℓ).
1 day ago
Preprints.org

Study on the Removal of Fluorescent Whitening Agent for Paper-mill Wastewater Reuse using the Submerged Membrane Bioreactor (SMBR) with Ozone Oxidation Process

The amount of ozone re- quired for the removal of the fluorescent whitening agent in the permeated water in SMBR was 6.67 g-O3/min, and the amount of ozone required to remove COD relative to the permeate water was calculated to remove 0.997 mg-COD for 1 mg of O3.
1 day ago
Preprints.org

structure property relationships

2 preprints

Structure-Property Relationships in Unsymmetric Bis(antiaromatics): Who Wins the Battle Between Pentalene and Benzocyclobutadiene?

According to the currently accepted structure-property relationships, aceno-pentalenes with angular shape (fused to the 1,2-bond of the acene) exhibit higher antiaromaticity than those with linear shape (fused to the 2,3-bond of the acene).
5 days ago
chemRxiv

Chemically Induced Splay Nematic Phase with Micron Scale Periodicity

This unexpected generation of the splay-nematic phase through binary mixtures offers a new route to materials which exhibit this phase which complements ongoing studies into structure-property relationships and could accelerate the development of technologies utilising this remarkable polar nematic variant.
3 days ago
chemRxiv

ozone oxidation

2 preprints

A Study on the Removal of Fluorescent Whitening Agent by Pretreatment Ozone Oxidation for MBR Process Application

The removal efficiencies of fluorescent whitening agents, a diaminostilbene disulfonic acid derivative by ozone oxidation were evaluated by UV254 Scan, COD, T-N and color using a synthetic wastewater sample (COD=433.0 mg/ℓ) and paper and paper mill wastewater (COD=157.2 mg/ℓ).
1 day ago
Preprints.org

Study on the Removal of Fluorescent Whitening Agent for Paper-mill Wastewater Reuse using the Submerged Membrane Bioreactor (SMBR) with Ozone Oxidation Process

In this study, effluent water was produced through Submerged Membrane Bio-Reactor (SMBR) process, which is a simple system and decomposes organic matter contained in wastewater with biological treatment process and performs solid-liquid separation, Especially, ozone oxidation treatment process is applied to effluent...
1 day ago
Preprints.org

removal of fluorescent whitening agent

2 preprints

A Study on the Removal of Fluorescent Whitening Agent by Pretreatment Ozone Oxidation for MBR Process Application

The removal efficiencies of fluorescent whitening agents, a diaminostilbene disulfonic acid derivative by ozone oxidation were evaluated by UV254 Scan, COD, T-N and color using a synthetic wastewater sample (COD=433.0 mg/ℓ) and paper and paper mill wastewater (COD=157.2...
1 day ago
Preprints.org

Study on the Removal of Fluorescent Whitening Agent for Paper-mill Wastewater Reuse using the Submerged Membrane Bioreactor (SMBR) with Ozone Oxidation Process

The amount of ozone re- quired for the removal of the fluorescent whitening agent in the permeated water in SMBR was 6.67 g-O3/min, and the amount of ozone required to remove COD relative to the permeate water was calculated to remove 0.997 mg-COD for 1 mg of O3.
1 day ago
Preprints.org

liquid liquid

2 preprints

Extraction on Paper, an Active Learning Technique to Facilitate Student Understanding of Liquid-Liquid Extraction

We envision this activity as a tool to help students understand and apply the chemical principles underlying liquid-liquid extractions outside of and before entering into a laboratory setting.
4 days ago
chemRxiv

Granulins modulate liquid-liquid phase separation and aggregation of TDP-43 C-terminal domain

These results constitute the first observation of direct interaction between GRNs and TDP-43 and suggest a mechanism by which the loss of PGRN function could lead to FTLD and ALS.
6 days ago
bioRxiv

Multiphase Complex Coacervate Droplets

Here, we show that the formation of hierarchically organized multiphase droplets with up to three coexisting layers is a generic phenomenon in mixtures of complex coacervates, which serve as models of charge-driven liquid-liquid phase separated systems.
5 days ago
chemRxiv

solid electrolyte

2 preprints

Adhesion and Surface Layers on Silicon Anodes Suppress Formation of c-Li3.75Si and Solid Electrolyte Interphase

TiO2 is slightly more effective in enhancing the capacity retention, most likely due to differences in the resulting solid electrolyte interphase (SEI).
1 day ago
chemRxiv

Rational Design of Quasi Zero-Strain NCM Cathode Materials for Minimizing Volume Change Effects in All-Solid-State Batteries

Unlike solid electrolytes, liquid electrolytes are somewhat capable of accommodating morphological changes.
4 days ago
chemRxiv