Evaluation of the performance of MP4-based procedures for a wide range of thermochemical and kinetic properties

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• 作者：Li-Juan Yu ; Wenchao Wan ; Amir Karton ; ^{amir.karton@uwa.edu.au" class="auth_mail" title="E-mail the corresponding author}
• 关键词：SCS-MP2 ; MP2.5 ; SCS-MP3 ; MP3.5 ; CCSD(T)
• 刊名：Chemical Physics
• 出版年：2016
• 出版时间：30 November 2016
• 年：2016
• 卷：480
• 期：Complete
• 页码：23-35
• 全文大小：568 K

文摘

We evaluate the performance of standard and modified MPn procedures for a wide set of thermochemical and kinetic properties, including atomization energies, structural isomerization energies, conformational energies, and reaction barrier heights. The reference data are obtained at the CCSD(T)/CBS level by means of the Wn thermochemical protocols. We find that none of the MPn-based procedures show acceptable performance for the challenging W4-11 and BH76 databases. For the other thermochemical/kinetic databases, the MP2.5 and MP3.5 procedures provide the most attractive accuracy-to-computational cost ratios. The MP2.5 procedure results in a weighted-total-root-mean-square deviation (WTRMSD) of 3.4 kJ/mol, whilst the computationally more expensive MP3.5 procedure results in a WTRMSD of 1.9 kJ/mol (the same WTRMSD obtained for the CCSD(T) method in conjunction with a triple-zeta basis set). We also assess the performance of the computationally economical CCSD(T)/CBS(MP2) method, which provides the best overall performance for all the considered databases, including W4-11 and BH76.