1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Benchmarking the multipole shielding polarizability/reaction field approach to solvation against QM/MM: Applications to the shielding constants of N-methylacetamide
Rent:
Rent this article for
USD
10.1063/1.3546033
/content/aip/journal/jcp/134/4/10.1063/1.3546033
http://aip.metastore.ingenta.com/content/aip/journal/jcp/134/4/10.1063/1.3546033

Figures

Image of FIG. 1.
FIG. 1.

Molecular structure of N-methylacetamide (NMA).

Image of FIG. 2.
FIG. 2.

(a) The basis set convergence of the nuclear magnetic shielding of nitrogen. (b) The basis set convergence of the nuclear magnetic shielding of hydrogen.

Image of FIG. 3.
FIG. 3.

(a) The basis set convergence of the first derivative, , of the nuclear magnetic shielding of nitrogen with respect to the electric field in the z-direction. (b) The basis set convergence of the first derivative, , of the nuclear magnetic shielding of hydrogen with respect to the electric field in the z-direction.

Image of FIG. 4.
FIG. 4.

(a) The basis set convergence of the second derivative, , of the nuclear magnetic shielding of nitrogen with respect to the electric field in the xx-direction. (b) The basis set convergence of the second derivative, , of the nuclear magnetic shielding of hydrogen with respect to the electric field in the xx-direction. Both Turbomole-TZVP, 6-311++G** and aug-pcS-2, give −450 .

Image of FIG. 5.
FIG. 5.

(a) The basis set convergence of the first derivative, , of the nuclear magnetic shielding of nitrogen with respect to the electric field gradient in the xx-direction. (b) The basis set convergence of the first derivative, , of the nuclear magnetic shielding of hydrogen with respect to the electric field gradient in the xx-direction.

Image of FIG. 6.
FIG. 6.

The field from the surrounding solvent at the positions of the different nuclei of NMA. The nitrogen is nucleus number 4, while the amide-hydrogen is nucleus number 6.

Tables

Generic image for table
Table I.

The nuclear magnetic shielding and the electric field and gradient derivatives of the shielding of the amide N and H atoms of the NMA molecule for different one-electron basis sets calculated using the geometry of the isolated NMA molecule. The nuclear magnetic shielding constant is given in ppm, the first derivatives is given as ppm/a.u., and the second derivative as . The relative deviations in % are with respect to the aug-pcS-3 results.

Generic image for table
Table II.

The nonvanishing components of the derivatives of the nuclear magnetic shielding with respect to the electric field and gradient of the amide N and H atoms of the isolated NMA molecule calculated using the aug-pcS-1 basis set. The first derivatives are given as ppm/a.u. and the second derivative as .

Generic image for table
Table III.

Solvent effects obtained using either the MSP/RF or QM/MM approaches for different one-electron basis sets. LF: linear field, QF: quadratic field, and LFG: linear field gradient. Diff. is the difference in the solvent shift of the nuclear magnetic shielding constant between the MSP/RF and QM/MM methods. All nuclear magnetic shieldings are given in ppm.

Generic image for table
Table IV.

Solvent effects calculated by using the averaged field from all MD-configurations and across all nuclei. “Averaged field” specifies the calculation where the field is directly included in the molecular Hamiltonian, while “expansion approach” refers to the MSP/RF approach. All calculations have been carried out at the level of B3LYP/aug-pcS-3.

Loading

Article metrics loading...

/content/aip/journal/jcp/134/4/10.1063/1.3546033
2011-01-25
2014-04-17
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Benchmarking the multipole shielding polarizability/reaction field approach to solvation against QM/MM: Applications to the shielding constants of N-methylacetamide
http://aip.metastore.ingenta.com/content/aip/journal/jcp/134/4/10.1063/1.3546033
10.1063/1.3546033
SEARCH_EXPAND_ITEM