Gasteiger atomic charges

Gasteiger J and M Marsili 1980. Iterative Partial Equalization of Orbital Electronegativity - Rapid Access to Atomic Charges. Tetrahedron 36 3219-3288. 

Gasteiger, J., Marsili, M. Iterative partial equalization of orbital electronegativity - a rapid access to atomic charges. Tetrahedron 1980, 36, 3219-3228. 

An example of quantum mechanical schemes is the oldest and most widely used Mulliken population analysis [1], which simply divides the part of the electron density localized between two atoms, the overlap population that identifies a bond, equally between the two atoms of a bond. Alternatively, empirical methods to allocate atomic charges to directly bonded atoms in a reasonable way use appropriate rules which combine the atomic electronegativities with experimental structural information on the bonds linking the atoms of interest. A widely used approach included in many programs is the Gasteiger-Hiickel scheme [1]. 

Gasteiger et al. returned to the initial I s) curve and maintained the explicit form of the curve [36]. For A they substituted various physicochemical properties such as atomic mass, partial atomic charges, and atomic polarizability. To obtain uniform length descriptors, the intensity distribution I s) is made discrete, calculating its value at a sequence of evenly distributed values of, for example, 32 or 64 values in the range of 0 - 3lA. The resolution of the molecule representation increases with higher number of values. The resulting descriptor is the 3D MoRSE (Molecular Representation of Structures based on Electron diffraction) Code. 

Zhang, J., Meinoder, T. and Gasteiger, J. (2006) Prediction of pJQ values for aliphatic carboxylic acids and alcohols with empirical atomic charge descriptors. /. Chem. Inf. Model., 46, 2256-2266. 

Gasteiger J, Marsili M. A new model for calculating atomic charges in molecules. Tetrahedron Lett, 1978 3181-3184. 

Some methods calculate atomic charges solely from information about the atoms present in the molecule and the way in which the atoms are connected. The great advantage of such methods is that they are very fast and can be used to calculate the charge distributions for large numbers of molecules (e.g. in a database). We will consider the Gasteiger and MarsiU method [Gasteiger and Marsili 1980] as an example. 

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