TABLE V.

Total computational time (min) and energy consumption (kWh) for DFT single point, analytic Hessian, TDDFT, and AXK calculations on {$\mathrm{T}\mathrm{h}{\left[{\mathrm{C}}_5{\mathrm{H}}_3{\left({\mathrm{S}\mathrm{i}\mathrm{M}\mathrm{e}}_3\right)}_2\right]}_3$}⁻ using TPSS and TPSSh functionals. 72 core orbitals were frozen for the AXK calculation. The calculations were performed on an Intel Xeon Gold 6148 @ 2.40 GHz CPU with 16 cores and on an AMD Ryzen 9 3900X @ 3.8 GHz CPU with 12 cores.

		Intel		AMD
			Energy		Energy
Calc.	Functional	t (min)	(kWh)	t (min)	(kWh)
DFTa	TPSS	3	0.01	2	0.01
	TPSSh	8	0.02	7	0.01
Hessianb	TPSS	270	0.68	197	0.34
	TPSSh	640	1.60	502	0.88
TDDFTc	TPSS	215	0.54	181	0.32
	TPSSh	1823	4.56	1880	3.29
AXKd	TPSS	166	0.42	307	0.54

^aSingle-point DFT calculation using the ridft module with the def-TZVP basis set on the Th atom and the def2-SV(P) basis set on the C, H, ans Si atoms, totaling 795 basis functions. The Stuttgart/Cologne ECP was used for Th.²⁰⁴

^bForce constant calculation for vibrational normal modes using the aoforce module with the same basis as the ridft calculations.

^cTDDFT calculation for the lowest 60 excitations using the escf module with the def-TZVP basis set on the Th atom and the def2-SVPD basis set on the C, H, and Si atoms.

^dRI-AXK calculation using the rirpa module with the def-TZVP basis set on the Th atom, the def2-TZVP basis set on the ring C atoms, and the def2-SV(P) basis set on the remaining C, H, and Si atoms.