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Vinyl chloride is an organochloride with the formula H 2 C=CHCl. It is also called vinyl chloride monomer (VCM) or chloroethene.It is an important industrial chemical chiefly used to produce the polymer polyvinyl chloride (PVC).
Molecular modelling encompasses all methods, theoretical and computational, used to model or mimic the behaviour of molecules. [1] The methods are used in the fields of computational chemistry, drug design, computational biology and materials science to study molecular systems ranging from small chemical systems to large biological molecules and material assemblies.
Figure 6 shows models of anthrax toxin, left (at a scale of approximately 20 Å/cm or 1:5,000,000) and green fluorescent protein, right (5 cm high, at a scale of about 4 Å/cm or 1:25,000,000) from 3D Molecular Design. Models are made of plaster or starch, using a rapid prototyping process.
It is based on the classic theory of polar liquids, as developed by Peter Debye and corrected by Lars Onsager to incorporate reaction field effects. [1] The model can be combined with quantum chemical calculations to formally derive a continuum model of solvent effects suitable for computer simulations of small and large molecular systems.
The ammonia molecule (NH 3) has three pairs of electrons involved in bonding, but there is a lone pair of electrons on the nitrogen atom. [1]: 392–393 It is not bonded with another atom; however, it influences the overall shape through repulsions. As in methane above, there are four regions of electron density.
Several of the CPK colors refer mnemonically to colors of the pure elements or notable compound. For example, hydrogen is a colorless gas, carbon as charcoal, graphite or coke is black, sulfur powder is yellow, chlorine is a greenish gas, bromine is a dark red liquid, iodine in ether is violet, amorphous phosphorus is red, rust is dark orange-red, etc.
Spartan is a molecular modelling and computational chemistry application from Wavefunction. [2] It contains code for molecular mechanics, semi-empirical methods, ab initio models, [3] density functional models, [4] post-Hartree–Fock models, [5] thermochemical recipes including G3(MP2) [6] and T1.
Molecular geometry refers to the spatial arrangement of atoms in a molecule and the chemical bonds that hold the atoms together and can be represented using structural formulae and by molecular models; [1] complete electronic structure descriptions include specifying the occupation of a molecule's molecular orbitals.