# Keyword reference¶

## .CUSTOM¶

Description...

## .XCGRID¶

Use the XCint grid instead of the default Dalton grid.

The radial grid is generated according to Lindh, Malmqvist, and Gagliardi [TCA 106(3), 178-187 (2001)].

The angular grid is generated according to Lebedev and Laikov [A quadrature formula for the sphere of the 131st algebraic order of accuracy, Russian Academy of Sciences Doklady Mathematics, Volume 59, Number 3, 1999, pages 477-481].

The keyword is followed by 3 lines:

```
.XCGRID
1.0d-12 # radial precision
86 # minimum number of angular points per radial shell
302 # maximum number of angular points per radial shell
```

The smaller the radial precision, the better.

The higher the values for minimum and maximum number of angular points, the better.

For the minimum and maximum number of angular points the code will use the following table and select the closest number with at least the desired precision:

```
{6, 14, 26, 38, 50, 74, 86, 110, 146, 170,
194, 230, 266, 302, 350, 434, 590, 770, 974, 1202,
1454, 1730, 2030, 2354, 2702, 3074, 3470, 3890, 4334, 4802,
4934, 5294, 5810}
```

The pruning is a primitive linear interpolation. The full angular grid is reached at 0.2 times the Bragg radius of the center.