Gauge Including/Invariant Atomic Orbitals

Such orbitals are known as London Atomic Orbitals (LAO) or Gauge Including/ Invariant Atomic Orbitals (GIAO). The effect is that matrix elements involving GIAOs... 

Whereas current computational techniques based on gauge-including atomic orbitals meet the requirement of translational invariance of calculated magnetic properties, they do not necessarily guarantee current/charge conservation. On the other hand, CTOCD schemes account for the fundamental identity between these constraints, which are expressed by the same quantum mechanical sum rules. 

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