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Keyword ORBITALS

This keyword controls the atomic orbital choice.
Options:
SPHERICAL / CARTESIAN
SPHERICAL Spherical atomic orbitals ($5d$, $7f$) are used. This is the default.
CARTESIAN Cartesian atomic orbitals ($6d$, $10f$) are used.
Description:
In deMon2k the spherical (see 4.4.7 for the definition of real spherical harmonic Gaussians) and Cartesian atomic orbitals have the general form (without normalization):
$\displaystyle \phi_{lm}({\bf r})$ $\textstyle =$ $\displaystyle r^l \, e^{- \alpha r^2} \, S_l^m(\vartheta, \phi)$ (16)
$\displaystyle \phi_{ijk}({\bf r})$ $\textstyle =$ $\displaystyle x^i \, y^j \, z^k \, e^{- \alpha r^2}$ (17)

Because spherical orbitals have no linear dependencies, they are the recommended choice for most applications. See 4.4.7 regarding CARTESIAN orbitals in the case of an atom.