Reparameterization of 12-6 Lennard-Jones potentials based on quantum mechanism results for novel tetrahedral N4 (Td) explosives

Abstract

can be condensed when the temperature is lowered than 250 K at 1 atm. or the pressure is higher than 55 atm. at the room temperature.Keywords Tetrahedral N4 · Parameterization of vdW potential · Three-body effect · Prediction of density

Automated Parameterization of Quantum Mechanically Derived Force Fields for Soft Materials and Complex Fluids: Development and Validation

“…To this end, a significant increase in computer power in the last two decades has permitted us to resort to accurate quantum mechanical (QM) methods, able to yield reliable reference data, over which specific FFs can be parameterized. Exploiting this possibility, several automated or semi-automated methods have been proposed that are able to deliver such quantum mechanically derived force fields (QMD-FFs). ,− Although all of these procedures are rooted in the possibility of deriving FF parameters based on selected QM data, they present different features, according to which they may be classified. One possible criterion is to consider the type of FF parameters employed: most of the aforementioned QMD-FF procedures concern either with the description of the single-molecule flexibility (intramolecular or valence FFs), ,,,,,,,,,, with the interaction between two or more species (intermolecular or noncovalent FFs), ,,,,,,,,,, or with both these aspects simultaneously. ,,,,,,,− , Alternatively, the different QMD-FFs can be also classified based on the complexity of their defining model functions.…”

“…Exploiting this possibility, several automated or semi-automated methods have been proposed that are able to deliver such quantum mechanically derived force fields (QMD-FFs). ,− Although all of these procedures are rooted in the possibility of deriving FF parameters based on selected QM data, they present different features, according to which they may be classified. One possible criterion is to consider the type of FF parameters employed: most of the aforementioned QMD-FF procedures concern either with the description of the single-molecule flexibility (intramolecular or valence FFs), ,,,,,,,,,, with the interaction between two or more species (intermolecular or noncovalent FFs), ,,,,,,,,,, or with both these aspects simultaneously. ,,,,,,,− , Alternatively, the different QMD-FFs can be also classified based on the complexity of their defining model functions. Indeed, exploiting the wealth of information contained in the parent QM description, more complex and physically motivated models can be adopted in the FF definition, allowing, for instance, to separately account for three-body terms, polarization effects, dispersion interactions, etc. ,,,,,,, …”

“…Indeed, exploiting the wealth of information contained in the parent QM description, more complex and physically motivated models can be adopted in the FF definition, allowing, for instance, to separately account for three-body terms, polarization effects, dispersion interactions, etc. ,,,,,,, However, the significant loss in computational speed has often limited their application in simulations of large and complex systems. In these cases, considering both the computational benefit and the straightforward availability in the most popular MD simulations engines, QMD-FFs can be more conveniently parameterized employing the standard simple potential functions, namely, 12–6 Lennard-Jones (LJ) potentials, point charges, harmonic potentials, and Fourier series. ,,,,,,,,,,,, …”

Development and Validation of Quantum Mechanically Derived Force-Fields: Thermodynamic, Structural, and Vibrational Properties of Aromatic Heterocycles

“…40−42 The several strategies that have been presented can be classified according to different criteria. First, these protocols concern either the description of a single molecule flexibility (intramolecular FFs), 16,17,20,21,24,25,29,31,38 the interaction between molecular pairs (intermolecular FFs), 18,19,27,27,30,32,34,36,37,39 or both. 8,22,23,26,28,33,35 Next, the parametrization procedure can be applied to a particular class of molecules (aromatic, aliphatic, etc.…”

“…As a matter of fact, following the pioneering work of Clementi’s − and Linse’s , groups, it is only in the past decade that, thanks to the massive increase of computational resources, there has been a renewed interest for quantum mechanically derived FFs (QMD-FFs), and several approaches have been proposed ,− and recently reviewed. − The several strategies that have been presented can be classified according to different criteria. First, these protocols concern either the description of a single molecule flexibility (intramolecular FFs), ,,,,,,,, the interaction between molecular pairs (intermolecular FFs), ,,,,,,,,, or both. ,,,,,, Next, the parametrization procedure can be applied to a particular class of molecules (aromatic, aliphatic, etc.…”