A study on the fragmentation of sulfuric acid and dimethylamine clusters inside an atmospheric pressure interface time-of-flight mass spectrometer

Sulfuric acid and dimethylamine vapours in the atmosphere can form molecular clusters, which participate in new particle formation events. In this work, we have produced, measured, and identified clusters of sulfuric acid and dimethylamine using an electrospray ionizer coupled with a planar-differential mobility analyser, connected to an atmospheric pressure interface time-of-flight mass spectrometer (ESI–DMA–APi-TOF MS). This set-up is suitable for evaluating the extent of fragmentation of the charged clusters inside the instrument. We evaluated the fragmentation of 11 negatively charged clusters both experimentally and using a statistical model based on quantum chemical data. The results allowed us to quantify the fragmentation of the studied clusters and to reconstruct the mass spectrum by removing the artifacts due to the fragmentation.

A study on the fragmentation of sulfuric acid and dimethylamine clusters inside an Atmospheric Pressure interface Time Of Flight Mass Spectrometer

Sulfuric acid and dimethylamine vapours in the atmosphere can form molecular clusters, which participate in new particle formation events. In this work, we have produced, measured and identified clusters of sulfuric acid and dimethylamine using an electrospray ionizer coupled with a planar differential mobility analyser, connected to an atmospheric pressure interface time-of-flight mass spectrometer (ESI–DMA–APi-TOF MS). This set-up is suitable for evaluating the extent of fragmentation of the charged clusters inside the instrument. We evaluated the fragmentation of 11 negatively charged clusters both experimentally and using a statistical model based on quantum chemical data. The results allowed us to quantify the fragmentation of the studied clusters and to reconstruct the mass spectrum removing the artifacts due to the fragmentation.

Effect of Selenium on TNAZ Molecule - A DFT Treatment

The present treatment deals with an unusual composite of TNAZ that is TNAZ+ nSe(n:1,2) within the constraints of density functional theory at the level of UB3LYP/6-31++G(d,p). TNAZ is an insensitive high explosive material. Since, selenium atom in its ground state has two unpaired electrons, the composites are considered in their singlet, triplet and quintet states. Selenium and TNAZ interact at different extents and the systems are electronically stable but TNAZ+2Se (singlet) structurally decomposes by the elongation of one of the geminally substituted nitro groups. Modeling studies indicate that the N-O bond elongation in the composite mentioned occurs only if azetidine ring is present with or without the nitramine bond. For the composites various structural, electronic and quantum chemical data have been harvested and discussed.

Destructive Reduction of TEX by Lithium-DFT Treatment

Interaction of lithium atom with TEX molecule which is a high density energetic material is considered within the restrictions of density functional theory at the level of UB3LYP/6-31++G(d,p). The results indicate that the lithium atom transfers an electron to TEX causing the rupture of one of C-N bonds of the structure. Some geometrical and quantum chemical data have been collected and discussed. A plausible mechanism has been suggested for the destructive reduction of TEX molecule.

Effect of Copper on 1,1-Diamino-2,2-dinitroethene - A DFT Treatment

Interaction of 1,1-diamino-2,2-dinitroethene which is a well known explosive called FOX-7 and copper atom is investigated computationally in the form of 1:1 composite, at the levels of UB3LYP/6-31++G(d,p) and UB3LYP/LANL2DZ within the restrictions of density functional theory. Some geometrical, spectral and quantum chemical data have been obtained and discussed. The both levels of computational approach yield geometries in accord with each other but LANL2DZ basis set produced unreasonable charges for the atoms of the composite. However, both of the methods indicate that copper atom donates some electron population to the organic component meantime the nitro groups change their conformation by twisting about the C-NO2 bonds. Thus, the push-pull character of the system varies which should affect some of the explosive properties, beside the others.

The MolSSI QCArchive Project: An Open-Source Platform to Compute, Organize, and Share Quantum Chemistry Data

<div>The Molecular Sciences Software Institute's (MolSSI) Quantum Chemistry Archive (QCArchive) project is an umbrella name that covers both a central server hosted by MolSSI for community data and the Python-based software infrastructure that powers automated computation and storage of quantum chemistry results.</div><div>The MolSSI-hosted central server provides the computational molecular sciences community a location to freely access tens of millions of quantum chemistry computations for machine learning, methodology assessment, force-field fitting, and more through a Python interface.</div><div>Facile, user-friendly mining of the centrally archived quantum chemical data also can be achieved through web applications found at https://qcarchive.molssi.org.</div><div>The software infrastructure can be used as a standalone platform to compute, structure, and distribute hundreds of millions of quantum chemistry computations for individuals or groups of researchers at any scale.</div><div>The QCArchive Infrastructure is open-source (BSD-3C), code repositories can be found at https://github.com/MolSSI, and releases can be downloaded via PyPI and Conda.</div>

The MolSSI QCArchive Project: An Open-Source Platform to Compute, Organize, and Share Quantum Chemistry Data

<div>The Molecular Sciences Software Institute's (MolSSI) Quantum Chemistry Archive (QCArchive) project is an umbrella name that covers both a central server hosted by MolSSI for community data and the Python-based software infrastructure that powers automated computation and storage of quantum chemistry results.</div><div>The MolSSI-hosted central server provides the computational molecular sciences community a location to freely access tens of millions of quantum chemistry computations for machine learning, methodology assessment, force-field fitting, and more through a Python interface.</div><div>Facile, user-friendly mining of the centrally archived quantum chemical data also can be achieved through web applications found at https://qcarchive.molssi.org.</div><div>The software infrastructure can be used as a standalone platform to compute, structure, and distribute hundreds of millions of quantum chemistry computations for individuals or groups of researchers at any scale.</div><div>The QCArchive Infrastructure is open-source (BSD-3C), code repositories can be found at https://github.com/MolSSI, and releases can be downloaded via PyPI and Conda.</div>

Calcium D-Pantothenate as Green Corrosion Inhibitor on Mild Steel in 240 ppm NaCl Solution

Corrosion inhibition of mild steel in 240 ppm NaCl solution using Calcium D-Pantothenate (Vitamin B5 ) as corrosion inhibitor is studied using electrochemical impedance, potentiodynamic polarization and weight loss studies. From the potentiodynamic polarization studies, icorr (corrosion current density) decreases with increasing the concentration of vitamin B5 (VB5 ). The CR (corrosion rate) decreases and the IE (inhibition efficiency) of VB5 increases on increasing the concentration of VB5 .Surface investigation using SEM, EDX spectra, UV-Vis, FTIR, electrochemical impedance, potentiodynamic polarization and adsorption isotherm parameter of VB5 in 240 ppm NaCl solution shows that VB5 can act asworthy corrosion inhibitors. Quantum chemical data obtained from density functional theory (DFT) calculations also agreed with the experimental outcomes.