By i_was_a_baby
2018.12.21

NMR(Nuclear Magnetic Resonance) is a physical phenomenon in which nuclei in a strong static magnetic field are perturbed by a weak oscillating magnetic field (in the near field and therefore not involving electromagnetic waves) and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. In NMR spectroscopy, the chemical shift is the resonant frequency of a nucleus relative to a standard in a magnetic field. Often the position and number of chemical shifts are diagnostic of the structure of a molecule. Chemical shifts are also used to describe signals in other forms of spectroscopy such as photoemission spectroscopy. In quantum chemistry, when the atom is in different chemical environment, the degree of screen electrons to nuclear is variable, and the chemical shifts can be different. So, in order to study the relationship with NMR and electron structure, several types of atomic charges can be employed in this article, such as ADCH, Hirshfeld, Mulliken, NPA, MK and RESP charges. As examples, Borane-derived complexes have been researched.

NMR.pdf