Table 3. Auxiliary Basis Set Study of the A^iso Parameter of Optimized HMI under Vacuum Using def2-TZVPP, Full Electron Treatment, Decontracted-s, and DLPNO-HFC1^a.

auxbasis	time (d:h:m:s)	Aiso(N) (MHz)
autoaux	9.7 h	29.6
cc-PWCVTZ/c	7.1 h	29.6
def2-TZVPP/c	7.1 h	29.4

^aThe DLPNO-HFC1 settings correspond to the “Default1” DLPNO-CCSD settings for accurate spin densities of ref (71).