# Selection Syntax

How to select things in Olex2
• 155: all symmetry generated atoms currently shown, which were generated by the given symmetry operation.
• rings NC5: all pyridine rings
• fvar -2: atoms where a parameter is linked to FVAR 2
• part 1: all atoms in PART 1
• isot: all isotropic atoms
• frag C5: the whole fragment containing C5
• $E: all atoms of the given type. E is a chemical element symbol or one of the following: * - all types, M - all metals, X - all halogens •$,E: all atoms, but of the E type.
• \$,H: all non-H atoms
• wbox: Shows the 3D selection box constructed for all/selected atoms. This box can be used to pack the structure or to crop the voids display/electron density maps. If the third argument (cell) is provided, the frame gets the dimensions of the unit cell rather than being rectangular (this box can be used for packing and 3D maps trimming/extending).
• ofile n: slects all atoms in the overlayed file n; if n is 0, elements of the currently focused file are selected

## sel atoms

where

• xatom.bai.mw > 20: Select all atoms where the atomic mass is larger than 20
• xatom.bai.z > 2: Select all atoms where the atomic number is greater than 2
• >>atoms: all atoms

## sel bonds

where

• xbond.length > 2: all bonds longer than 2 Å
• xbond.b.bai.z == 1: all bonds where the lightest atoms is H
• >>atoms: all atoms