Del Bene Janet E, Alkorta Ibon, Elguero José
Department of Chemistry, Youngstown State University, Youngstown, Ohio, 44555, USA.
Instituto de Química Médica (IQM-CSIC), Juan de la Cierva, 3, 28006, Madrid, Spain.
Chemphyschem. 2020 Apr 20;21(8):741-748. doi: 10.1002/cphc.202000099. Epub 2020 Mar 17.
Ab initio MP2/aug'-cc-pVTZ calculations have been carried out to investigate H CO : PXH pnicogen-bonded complexes and HCO H : PXH complexes that are stabilized by pnicogen bonds and hydrogen bonds, with X=NC, F, Cl, CN, OH, CCH, CH , and H. The binding energies of these complexes exhibit a second-order dependence on the O-P distance. DFT-SAPT binding energies correlate linearly with MP2 binding energies. The HCO H : PXH complexes are stabilized by both a pnicogen bond and a hydrogen bond, resulting in greater binding energies for the HCO H : PXH complexes compared to H CO : PXH . Neither the O-P distance across the pnicogen bond nor the O-P distance across the hydrogen bond correlates with the binding energies of these complexes. The nonlinearity of the hydrogen bonds suggests that they are relatively weak bonds, except for complexes in which the substituent X is either CH or H. The pnicogen bond is the more important stabilizing interaction in the HCO H : PXH complexes except when the substituent X is a more electropositive group. EOM-CCSD spin-spin coupling constants J(O-P) across pnicogen bonds in H CO:PXH and HCO H : PXH complexes increase as the O-P distance decreases, and exhibit a second order dependence on that distance. There is no correlation between J(O-P) and the O-P distance across the hydrogen bond in the HCO H : PXH complexes. J(O-P) coupling constants for complexes with X=CH and H have much greater absolute values than anticipated from their O-P distances.
已开展从头算MP2/aug'-cc-pVTZ计算，以研究H CO : PXH氮族元素键合配合物以及通过氮族元素键和氢键稳定的HCO H : PXH配合物，其中X = NC、F、Cl、CN、OH、CCH、CH 和H。这些配合物的结合能对O - P距离呈现二阶依赖性。DFT - SAPT结合能与MP2结合能呈线性相关。HCO H : PXH配合物通过氮族元素键和氢键两者得以稳定，相较于H CO : PXH ，这使得HCO H : PXH配合物具有更大的结合能。横跨氮族元素键的O - P距离以及横跨氢键的O - P距离均与这些配合物的结合能无关。氢键的非线性表明它们是相对较弱的键，但取代基X为CH 或H的配合物除外。在HCO H : PXH配合物中，除取代基X为更正电基团的情况外，氮族元素键是更重要的稳定相互作用。H CO:PXH和HCO H : PXH配合物中横跨氮族元素键的EOM - CCSD自旋 - 自旋耦合常数J(O - P)随着O - P距离的减小而增大，并且对该距离呈现二阶依赖性。在HCO H : PXH配合物中，J(O - P)与横跨氢键的O - P距离之间不存在相关性。取代基X为CH 和H的配合物的J(O - P)耦合常数的绝对值比根据其O - P距离预期的要大得多。
