The Units keyword controls the units used in the Z-matrix for distances and angles and related values, such as step-sizes in numerical differentiation. The defaults are Angstroms and degrees.
Distances are in Angstroms (this is the default).
Distances are in atomic units (Bohrs).
Angles are in degrees (the default).
Angles are in radians.
The Charge, Cube and Massage keywords are not affected by the setting of the Units keyword, and their input is always interpreted in units of Angstroms and degrees.