1D attributes

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The attributes list the caracteristics of signals found in spectra. List of signal attributes (1D spectra)

Note that they should apear in this order!

S= Multiplicity (string)
J= Scalar coupling (string)
N= number of nuclei (rounded number of atoms) (int)
L= Label of the signal (string)
E= Integral (crude integrals) (float)
I= Intensity (float)
W= Width (float)
T1= T1 relaxation time in second (float)
T2= T2 relaxation time in second (float)
Diff= for diffusion rate in m2/s-1 (float)

Examples of signal attribute in 1D spectrum

Chemical shifts are give with four digits after the period.

Examples of a doublet in 1D 1H spectrum: "4.182 (s, 2H, H-(C3))"

4.1823, S=d, N=2, L=H-(C3) 

Examples of a typical signals in 1D 13C spectra: "14.1823 CH2,C(5)"

14.1823, S=2, L=C(5) 

Examples of a a negative signal for CH2,C(5) a DEPT 13C spectra

14.1823, S=2, L=C(5), I=-95.12


S= Multiplicity


s singlet
d doublet
t triplet
q quartet
... ...
hept heptet
bs broad singlet
m multiplet

In case of overlap, second-order effects, use "m". This is meant to be the apparent multiplicity. For example a dd with similar coupling will look as a triplet, can be called "t".

J= Scalar coupling

J= Scalar coupling (unassigned)

Couplings in Hz with one digit after the period separated by the separator.

J=9.3, 4.8

following the couplings labels may be given in parenthesis to assign the coupling.

J= Scalar coupling (assigned)

Scalar coupling are given with two digits following the period For a signal assigned to "a",


means:J(a,b)=9.3 Hz

J=9.30(b), 4.80(c) 

means: J(a,b)=9.3 Hz J(a,c)=4.8 Hz

See also, <NMREDATA_J> tag where assigned coupling should be compiled.

N= number of nuclei

Number of nuclei.

For 1D 1H, spectra, (1 for CH, 2 for CH2, N for multiplet, where N is the number of proton in the range)

For 1D 13C, spectra, (0 for quaternary carbons, N for CHN, where N is the number of proton bound to the carbon)

This reflects the value of the integrals, but it is not the value of the integral. The value of the integral can be specified using the "E=" attribute.

L= Label

The label (according to list in the <NMR_ASSIGNMENT> tag).

E= Signal Integral

E integral (in arbitrary unit).

I= Signal intensity

I intensity (in arbitrary unit).

W= Signal width

W widht of the signal at half height (in Hz).

T1/T2= Relaxation time

Results of relaxation measurements, T1, T2, etc. can be given in seconds as:

4.8000, S=q, E=2, L=a, T1=0.7

Diff= Diffusion rate

Diffusion rates in m2/s-1

4.8000, S=q, E=2, L=a, Diff=1.12e-9