Kaolinite plays a prominent role in human activities ( Schroeder and Erickson, 2014). paper coating, paint, ceramics, etc.) ( Murray and Keller, 1993 Murray, 2007). Kaolinite is very abundant in nature and large quantities are used in classical applications (e.g.
Both the 1H and 27Al MAS NMR studies at different magnetic fields afforded important information about the local environments of the kaolinite hydroxyl groups and structural Al(III).Ĭlay minerals are known for many unique chemical and physical properties that make them attractive starting materials for a vast variety of applications ( Johnston, 2010 Bergaya and Lagaly, 2013). Increased quadrupolar constants were observed and showed the major perturbations of the local Al symmetry that resulted from DMSO intercalation.
The two octahedral Al(III) sites are not equivalent and can be distinguished in the low-field spectral simulation. The 27Al MAS NMR spectra of KGa-1b obtained under different magnetic fields revealed that most of the quadrupolar effects were highly reduced at 21.1 T, whereas the spectra at lower field, 4.7 T, were dominated by quadrupolar effects. The 1H MAS NMR chemical shifts of the two methyl groups in DMSO-K are not equivalent and can be attributed to the 2.9 and 4.2 ppm peaks. In the present work, the 1H MAS NMR chemical shifts of KGa-1b were unambiguously attributed to the internal surface hydroxyls at 2.7 ppm and to the internal hydroxyls at 1.7 ppm. Because quadrupolar interactions are sensitive to the local octahedral Al(III) geometry, solid-state 27Al NMR can follow subtle structural modifications in the octahedral sheet. 1H NMR, nevertheless, can give unique information about kaolinite hydroxyls. The use of 1H and 27Al MAS NMR for this purpose has been relatively rare. Well developed characterization methods are essential to define the structural modifications of kaolinite, and MAS NMR is a useful complement to other techniques. Intercalating DMSO into kaolinite to form the DMSO-K intercalate is, thus, a particularly useful first step toward the intercalation of a large variety of molecules, including polymers and ionic liquids. Once the interlayer space is expanded, the intercalated compounds can be replaced in a second step. The interlayer chemistry of kaolinite (K) was examined by intercalating a select group of highly polar organic molecules or salts into kaolinite as a first step. In this work, unique structural information on kaolinite and on kaolinite dimethylsulfoxide (DMSO) intercalate were provided by solid-state 1H and 27Al magic-angle spinning (MAS) NMR. I would appreciate any others.Nuclear magnetic resonance (NMR) provides a powerful tool to describe local nuclear environments. I think this is significant.įor the sake of completeness- I am doing the programming in R.ĮDIT: please see this post in stackoveflow. So far this is what i have learnt:ġ.) The first column represents the spectral point position (ppm)Ģ.) The second column represents the intensity of each peak.ģ.) notice that in the second column there are some numbers which are not perfectly aligned but are closer to the first column. And how exactly they are converted into their appropriate values in the spectrum.
#MESTRENOVA NMR BASE PEAKS HOW TO#
So i need to know how to interpret these numbers. My program has to identify the peaks from this data. The complete list runs into thousands of lines. For Carnitine this is what the ascii file looks like(this is not the complete list. So i converted the 1r files of the Bruker NMR spectra to ASCII. My program needs to work on the actual spectrum. I have some Bruker NMR spectra that i am using to create a program as part of a project.
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