Full configuration interaction benchmark calculations

Full configuration interaction (Cl) calculations for the shieldings in H2 (50) and BH molecules have demonstrated that the CCSD(T) results are sufficiently close to the full Cl results, so that for practical purposes, the CCSD(T) calculations may be considered as the benchmark calculations for each molecule, against which other methods such as density functional methods may be tested. 

Knowles, J. Chem. Phys., 85, 1469 (1986). Benchmark Full Configuration Interaction Calculations on HF and NH2. 

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