# Orbital Modify

- Type
- Scope
- Volume
- Position
- View

Change here the numerical representation of a single orbital or a list of orbitals.

To modify an orbital, click over its graphic image, or write its id on the Orbital entry. To modify a list of orbitals, press the button List (after creating the list of orbitals with Orbital->Select). Parameters for empty entries or Local choices remain unchanged.

To change an orbital name write the new name in the Orbital entry, followed by the orbital number (GAMGI needs the number to identify the orbital). To change the name for a list of orbitals, press List first and then write the new common name in the Name entry.

### Style

There are two ways to describe orbitals in GAMGI: as a cloud of random points describing all the regions of space where the probability density is above a specified value, the Wired approach; 2) as the outer isosurface linking points with the specified probability density, the Solid approach. Please note that in s orbitals, there are several different isosurfaces with the same probability density, GAMGI shows only the most external one.

### Density

Defines the probability density (probability / volume) value used to accept points in Wired mode (when they are above this threeshold) or to build points in Solid mode (where they have exactly this threeshold).

The low default value (1E-6)) was chosen to guarantee that all the inter-node regions are visible with default parameters. For example, the six inter-node regions of orbital 6s are all visible with the default parameters.

### Radius

Defines the sampling volume that is scanned when building an orbital. In Wired mode, the sampling volume is the sphere with this radius. In Solid mode, the sampling volume is the cube containing this sphere.

For each orbital, the default radius is obtained calculating first the distance for the last maximum of the radial probability density (the first Bohr radius, for orbital 1s), then adding an offset (to guarantee a proper sampling region, currently 2.0 Angstrom) and finally increasing the radius untill the probability density becomes lower in all directions than the default probability density.

### Sampling

In Wired mode, random points are generated and tried untill the number of accepted points equals Sampling. By default Sampling is 50000 x N, where N is the main quantum number.

In Solid mode, a sampling cubic grid is built for each octant, with Sampling slices on each dimension. By default Sampling is 50.

### Seed

In Wired mode, sampling points are randomly positioned using a sequence of (pseudo) random numbers, generated from a Seed initiator. Using different seeds, different random sequences and final results will be produced. Using the same seed, the same results will be obtained.
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