2001 Fiscal Year Final Research Report Summary
Calculation of NMR chemical shifts using relativistic wave functions
| Project/Area Number |
12640482
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Physical chemistry
|
|---|
| Research Institution | Kitami Institute of Technology |
|---|
Principal Investigator |
FUKUI Hiroyuki Kitami Institute of Technology, Department of Engineering, Professor, 工学部, 教授 (30002041)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
BABA Takehisa Kitami Institute of Technology, Department of Engineering, Technical Assistant Professor, 工学部, 教務職員 (80261402)
|
|---|
| Project Period (FY) |
2000 – 2001
|
| Keywords | Dirac equation / NMR / chemical shift / relativistic effect / DKH transformation |
|---|
| Research Abstract |
A two-component relativistic SCF perturbation theory, based on the Douglas-Kroll-Hess (DKH) transformation, was applied to the calculation of nuclear magnetic shielding tensors of hydrogen halides, HX (X=F, Cl, Br, I). Calculations were performed via the unrestricted coupled Hartree-Fock (CHF) scheme using gauge-including atomic orbitals (GIAOs) at four different levels. At the level I calculation, both the scalar relativistic (SR) and spin-orbit (SO) interactions were included in the zeroth-order Hamiltonian. However, the magnetic perturbation Hamiltonians were treated nonrelativistically. The results of these calculations indicated a large interplay between the SR and SO interactions. The level I calculation was found to be insufficient to explain the full relativistic effect on the halogen atom shielding. In order to reproduce the full relativistic effect, the mass-velocity effect on the magnetic perturbation Hamiltonians was introduced at the level II to IV calculations. Inclusion of the mass-velocity effects into all of the perturbation Hamiltonians, made at levels III and IV, improved the results greatly. The cross term between the nuclear attraction potential and the magnetic vector potential was introduced approximately in level IV. The level III calculation agreed most closely with the four-component relativistic random phase approximation (RPA) calculation by Visscher et al.
|
Research Products
(2 results)
