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[1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [4] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.
Hofmann's 1865 ball-and-stick model of methane (CH 4). Later discoveries disproved this geometry. In 1865, German chemist August Wilhelm von Hofmann was the first to make ball-and-stick molecular models. He used such models in lecture at the Royal Institution of Great Britain. Specialist companies manufacture kits and models to order.
Molecular models may be created for several reasons – as pedagogic tools for students or those unfamiliar with atomistic structures; as objects to generate or test theories (e.g., the structure of DNA); as analogue computers (e.g., for measuring distances and angles in flexible systems); or as aesthetically pleasing objects on the boundary of ...
A pure substance is composed of only one type of isomer of a molecule (all have the same geometrical structure). Structural isomers have the same chemical formula but different physical arrangements, often forming alternate molecular geometries with very different properties.
Methane (US: / ˈ m ɛ θ eɪ n / METH-ayn, UK: / ˈ m iː θ eɪ n / MEE-thayn) is a chemical compound with the chemical formula CH 4 (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas.
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.
The methane molecule (CH 4) is tetrahedral because there are four pairs of electrons. The four hydrogen atoms are positioned at the vertices of a tetrahedron, and the bond angle is cos −1 (− 1 ⁄ 3) ≈ 109° 28′. [16] [17] This is referred to as an AX 4 type of molecule. As mentioned above, A represents the central atom and X represents ...
A notable molecule editor is a computer program for creating and modifying representations of chemical structures.. Molecule editors can manipulate chemical structure representations in either a simulated two-dimensional space or three-dimensional space, via 2D computer graphics or 3D computer graphics, respectively.