Description

The Charge keyword requests that a background charge distribution be included in the calculation. The charge distribution is made up of point charges [ Hall84 G. G. Hall and C. M. Smith, “Fitting electron-densities of molecules,” Int. J. Quantum Chem., 25 (1984) 881-90. DOI: qua.560250510 , Smith86 C. M. Smith and G. G. Hall, “Approximation of electron-densities,” Theor. Chem. Acc., 69 (1986) 63-69. DOI: BF00526293 ].

入力

Input

By default, the charges are read from the input stream, one per line, in this format:

x y z charge

where x,y,z are the coordinates in the standard orientation (in the units specified by the Units keyword and defaulting to Angstroms), and charge is the charge.

オプション

Options

Angstroms

Indicates that input charge locations are specified in Angstroms.

Bohrs

Indicates that input charge locations are specified in Bohrs.

Check

Reads the background charge distribution from the checkpoint file.

適用範囲

Availability

Single point energies, optimizations and frequencies. Not valid with semi-empirical methods or PBC.

関連キーワード

Related Keywords

Units

実例

Examples

To perform geometry optimizations in the presence of background charges, you must use Opt=Z-Matrix NoSymm keywords and define the input geometry either in traditional Z-matrix coordinates or symbolic Cartesian coordinates. Here is an example:

# B3LYP/6=31G(d) Opt=Z-Matrix Charge NoSymm
 
Water with point charges
 
0,1
O -0.75 -0.94 0.0
H 0.21 -0.94 0.0
H-1.07 -0.0 0.0
 
2.0  2.0 2.0 1.2
2.0 -2.0 2.0 1.1