Reassessment of large dipole moment enhancements in crystals: a detailed experimental and theoretical charge density analysis of 2-methyl-4-nitroaniline.

摘要: The molecular dipole moment of MNA in the crystal has been critically reexamined, to test conclusion from an earlier experimental charge density analysis that it was substantially enhanced due a combination strong intermolecular interactions and field effects. X-ray neutron diffraction data have carefully measured at 100 K supplemented with ab initio Hartree−Fock calculations. Considerable care taken measurement reduction excluded most systematic errors, sources error their effects on electron investigated. derived fit theoretical structure factors assisted determination scale thermal motion model. enhancement for is much less than reported previously only order 30−40% (∼2.5 D). In addition moment, deformation maps, bond critical ...