Supporting Information for "W4neo: leveraging $\Lambda$ coupled cluster as the `new engine option' for accurate computational thermochemistry approaches"

(a) Microsoft Excel workbook with all energies and statistics.(b) PDF document containing the following supplementary figures and tables: Box plots of CCSDTQ5 – CCSDTQ contributions to TAEs (Fig. S1), CCSDTQ(5)$_\Lambda$ – CCSDTQ contributions (Fig. S2), CCSDTQ-CCSDT(Q) and CCSDTQ-CCSDT(Q)$_\Lambda$ basis set convergence (Figs. S3 and S4, respectively), CCSDT(Q)-CCSDT differences (Fig. S5);Table S1: Relative errors (kcal/mol) of T$_4$ – (Q) and T$_4$ – (Q)$_\Lambda$ compared to T$_4$ – (Q)/VQZ(g,d) and T$_4$ – (Q)$_\Lambda$/VQZ(g,d), respectively; Table S2: Wall clock times (min) of composite approaches for selected species; Table S3: Wall clock times per post-CCSD(T) step of each composite approach; Table S4: Post-CCSD(T) step time (\% of total wall time) for each composite approach. <br>