Naslov
Theoretical Simulation of Conformational Influence on NMR Chemical Shielding Anisotropy

Autori
Smrečki, Vilko ; Mueller, Norbert

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts / K. Bergant ; M. Franko ; T. Trampuž-Kajsersberger ; P. Trebše ; V. Žigman - Nova Gorica : Nova Gorica Polytechnic, Nova Gorica, Slovenia, 2005

Skup
14th International Symposium "Spectroscopy in Theory and Practice"

Mjesto i datum
Nova Gorica, Slovenija, 10.04.2005. - 13.04.2005

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
-

Sažetak
The experimental methodology of NMR spectroscopy is not (yet) able to determine chemical shielding anisotropy (CSA) tensors of all nuclei in complex molecules easily. It is therefore justified to assess the influences of structural parameters using computational techniques to estimate experimentally unknown or inaccessible data and chart the scope and limitations of structural information derived from future experiments. In this work the Gaussian98 program package was used for geometry optimization and NMR parameters calculation by DFT (B3LYP) employing the Gauge-Invariant Atomic Orbital (GIAO) approach. Capped alanine dipeptide and octapeptide are molecular models used in the simulation of protein secondary structure elements and CSA calculations. For each backbone atom of the dipeptide we analyzed the CSA tensor by itself and, additionally, in the context of cross correlated relaxation with selected dipolar interactions. This was to accommodate both the needs of solid state and liquid state experiments. Moreover, we introduced the octapeptide model in order to account for the hydrogen bonding influences. We will present here an excerpt from a compilation of multinuclear CSA data on the model peptides covering the accessible part of the Ramachandran conformational map obtained by DFT simulations and discuss an impact our results may have on the design of future experiments. Acknowledgement This work was supported in part by the Lise Meitner fellowship of the Austrian Science Fund (FWF M677), FWF project P15380, Austrian Croatian joint research project 911-02/03-06 (ÖAD-Project 13/04), and the Ministry of Science, Education and Sport of the Republic of Croatia project P0098059.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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