LNMRLEG: Difference between revisions

Revision as of 15:03, 17 February 2026

LNMRLEG = .TRUE.| .FALSE.

Default: LNMRLEG

= .FALSE.

Mind: Available as of VASP 6.6.0

Description: LNMRLEG controls whether VASP prints NMR properties to OUTCAR according to the old format (pre-version 6.6.0).

In version 6.6.0, the output format for NMR properties was updated. The legacy format is as presented below (see LCHIMAG for the current version). The chemical shielding tensors, UNSYMMETRIZED TENSORS and SYMMETRIZED TENSORS are printed. From the three diagonal values of the symmetrized tensor, the isotropic chemical "shift" [math]\displaystyle{ \delta_{\mathrm{iso}}\mathrm{[VASP]} }[/math], span [math]\displaystyle{ \Omega }[/math], and skew [math]\displaystyle{ \kappa }[/math] are calculated and printed, see Ref. ^[1] for unambiguous definitions. Note that [math]\displaystyle{ \kappa }[/math] is ill-defined if [math]\displaystyle{ \Omega = 0 }[/math]. Units are ppm, except for the skew. A typical output is given below:

                                                                                                          
   ---------------------------------------------------------------------------------
    CSA tensor (J. Mason, Solid State Nucl. Magn. Reson. 2, 285 (1993))
   ---------------------------------------------------------------------------------
               EXCLUDING G=0 CONTRIBUTION             INCLUDING G=0 CONTRIBUTION
           -----------------------------------   -----------------------------------
    ATOM    ISO_SHIFT        SPAN        SKEW     ISO_SHIFT        SPAN        SKEW
   ---------------------------------------------------------------------------------
    (absolute, valence only)
       1    4598.8125      0.0000      0.0000     4589.9696      0.0000      0.0000
       2     291.5486      0.0000      0.0000      282.7058      0.0000      0.0000
       3     736.5979    344.8803      1.0000      727.7550    344.8803      1.0000
       4     736.5979    344.8803      1.0000      727.7550    344.8803      1.0000
       5     736.5979    344.8803      1.0000      727.7550    344.8803      1.0000
   ---------------------------------------------------------------------------------
    (absolute, valence and core)
       1   -6536.1417      0.0000      0.0000    -6547.9848      0.0000      0.0000
       2   -5706.3864      0.0000      0.0000    -5718.2296      0.0000      0.0000
       3   -2369.4015    344.8803      1.0000    -2381.2446    344.8803      1.0000
       4   -2369.4015    344.8803      1.0000    -2381.2446    344.8803      1.0000
       5   -2369.4015    344.8803      1.0000    -2381.2446    344.8803      1.0000
   ---------------------------------------------------------------------------------
    IF SPAN.EQ.0, THEN SKEW IS ILL-DEFINED
   ---------------------------------------------------------------------------------

The isotropic chemical shielding for each atom, excluding and including G=0 contributions, as well as the span and skew (descriptions of asymmetry), follow. Finally, core contributions are taken into account for the ISO_SHIFT, SPAN, and SKEW.

Important:

The columns excluding the [math]\displaystyle{ \mathbf{G=0} }[/math] contribution are useful for supercell calculations on molecules.
The columns including the [math]\displaystyle{ \mathbf{G=0} }[/math] contribution are for crystals.
The upper block gives the shielding due to only the electrons included in the SCF calculation.
The lower block has the contributions due to the frozen PAW cores added. These core contributions are rigid ^[2]. They depend on POTCAR and are isotropic, i.e. affect neither SPAN nor SKEW.

Mind: In legacy mode, the chemical shift (the negative of the chemical shielding) is always printed, even if LNMRSHIELD = .TRUE..

References

[mason:ssn:1993-1] J. Mason, Conventions for the reporting of nuclear magnetic shielding (or shift) tensors suggested by participants in the NATO ARW on NMR shielding constants at the University of Maryland, College Park, July 1992, Solid State Nucl. Magn. Reson. 2, 285 (1993).

[gregor:jcp:1999-2] T. Gregor, F. Mauri, and R. Car, A comparison of methods for the calculation of NMR chemical shifts, J. Chem. Phys. 111, 1815 (1999).

[1]

[2]

@@ Line 7: / Line 7: @@
 Description: {{TAG|LNMRLEG}} controls whether VASP prints NMR properties to {{FILE|OUTCAR}} according to the old format (pre-version 6.6.0).
 ----
-{{not released}}
 In version 6.6.0, the output format for NMR properties was updated. The legacy format is as presented below (see {{TAG|LCHIMAG}} for the current version). The chemical shielding tensors, <code>UNSYMMETRIZED TENSORS</code> and <code>SYMMETRIZED TENSORS</code> are printed. From the three diagonal values of the symmetrized tensor, the isotropic chemical "shift" <math>\delta_{\mathrm{iso}}\mathrm{[VASP]}</math>, span <math>\Omega</math>, and skew <math>\kappa</math> are calculated and printed, see Ref. {{Cite|mason:ssn:1993}} for unambiguous definitions. Note that <math>\kappa</math> is ill-defined if <math>\Omega = 0</math>. Units are ppm, except for the skew. A typical output is given below:
@@ Line 44: / Line 44: @@
 {{NB|mind|In legacy mode, the chemical shift (the negative of the chemical shielding) is always printed, even if {{TAG|LNMRSHIELD}} {{=}} .TRUE..}}
 == Related tags and articles ==
-{{FILE|LCHIMAG}}
+{{TAG|LCHIMAG}}, {{TAG|INMRPRINT}}
 == References ==
-<!-- [[Category:INCAR tag]][[Category:NMR]] -->
+[[Category:INCAR tag]][[Category:NMR]]