𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Ab initio simulations of the NMR spectra of β-alanine conformers

✍ Scribed by Jan Cz. Dobrowolski; Joanna E. Rode; Joanna Sadlej

Publisher
Elsevier
Year
2011
Tongue
English
Weight
500 KB
Volume
964
Category
Article
ISSN
2210-271X

No coin nor oath required. For personal study only.

✦ Synopsis

The NMR shielding and indirect spin-spin coupling constants are calculated for 10 most stable conformers of b-alanine, using the B3LYP/aug-cc-pVTZ-su-1 level. In this study the focus is on determination of conformational effects and the intramolecular hydrogen bond on the NMR parameters for b-alanine conformers. Numerous correlations were detected between geometrical, topological and NMR parameters. The 13 C chemical shifts show dependence on intramolecular hydrogen bonds. The 15 N chemical shifts seem to be sufficient in supporting the conformational analysis. Some 1 J-coupling constant correlate with both the bond critical point electron density and the Laplacian. The vicinal proton-proton 3 J-coupling constants show clearly the local arrangements around the respective axes. Therefore, NMR parameters along with the quantum chemical calculations may be able to discriminate between conformers.

📜 SIMILAR VOLUMES

Conformational study of the tricyclic se
Conformational study of the tricyclic sesquiterpene β-panasinsene aided by ab initio calculations and simulated 1H NMR parameters
✍ César A. Flores-Sandoval; Carlos M. Cerda-García-Rojas; Pedro Joseph-Nathan 📂 Article 📅 2001 🏛 John Wiley and Sons 🌐 English ⚖ 166 KB

## Abstract __Ab initio__ calculations of the tricyclic sesquiterpene β‐panasinsene (**1**) provided theoretical H—C—C—H dihedral angles that allowed us to predict the corresponding ^1^H–^1^H vicinal coupling constant values, using a generalized Karplus‐type equation. These values, together with th

AB INITIO MO AND MONTE CARLO SIMULATION
AB INITIO MO AND MONTE CARLO SIMULATION STUDY ON THE CONFORMATION OF L-ALANINE ZWITTERION IN AQUEOUS SOLUTION
✍ Osamu Kikuchi; Toshio Watanabe; Yasushi Ogawa; Hideto Takase; Ohgi Takahashi 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 190 KB 👁 2 views

The conformation of the L-alanine zwitterion (ALAZ) in aqueous solution was examined by an ab initio MO method including the solvent effect with the generalized Born (GB) equation. The geometry optimization with the 6-31++G\* basis set gave the (, ) = (80, 8) conformation as the most stable conforma

Cyclopropanes: Calculation of NMR spectr
Cyclopropanes: Calculation of NMR spectra by ab initio methodology
✍ Ronald R. Sauers 📂 Article 📅 1998 🏛 Elsevier Science 🌐 French ⚖ 705 KB

1H and 13C nuclear magnetic resonance chemical shifts for a select group of cyclopropyl systems were calculated using ab initio/gauge-independent atomic orbital methodology. Long range nucleus independent chemical shifts attributable to cyclopropane ring currents were estimated. The results demonstr

Ab initio simulation of the photoelectro
Ab initio simulation of the photoelectron spectra of HCO− and DCO−
✍ Kurt M. Christoffel; Joseph S. Bittman; Joel M. Bowman 📂 Article 📅 1987 🏛 Elsevier Science 🌐 English ⚖ 494 KB

Large scale, vibrational CI calculations using a global ab initio potential energy surface are used to calculate multidimensional Franck-Condon overlaps from the ground vibrational state of HCO-and DCO-to all final bound and several quasibound vibrational states of HCO and DCO. The resulting Franck-