An Ab initio and chemical shielding tensors calculations for Nucleotide 5’-Monophosphates in the Gas phase

Authors

  • G. Ghassemi Not-mentioned
  • M. Monajemi Not-mentioned
  • M.A Seyed Sajjadi Not-mentioned
  • R. Sayyadi Not-mentioned
Abstract:

Structural and magnetic properties of purine and pyrimidine nucleotides (CMP, UMP, dTMP, AMP, GMP, IMP) were studied at different levels of ab initio molecular orbital theory. These calculations were performed at the hartree-fock level and density functional B3LYP methods. Geometries were fully optimized by following Cs symmetry restrictions. The standard 6-31G** basis set which includes polarization and diffuse functions, was used for all the calculations.  The gauge-invariant atomic atomic orbital (GIAO) method and the continuous-set-of-gauge-transformation (CSGT) procedure was employed to calculate atomic shielding tensors of the nucleotides using density theory at the B3LYP/6-31g** and HF/6-31g** level. The calculated chemical shifts were used to aid in assigning in the NMR spectra.

Upgrade to premium to download articles

Sign up to access the full text

Already have an account?login

similar resources

an ab initio and chemical shielding tensors calculations for nucleotide 5’-monophosphates in the gas phase

structural and magnetic properties of purine and pyrimidine nucleotides (cmp, ump, dtmp, amp, gmp, imp) were studied at different levels of ab initio molecular orbital theory. these calculations were performed at the hartree-fock level and density functional b3lyp methods. geometries were fully optimized by following cs symmetry restrictions. the standard 6-31g** basis set which includes polari...

full text

Ab Initio Calculation 29Si NMR Chemical Shift Studies on Silicate Species in Aqueous and Gas Phase

Nowadays NMR spectroscopy becomes a powerful tool in chemistry because of the NMR chemical shifts. Hartree–Fock theory and the Gauge-including atomic orbital (GIAO) methods are used in the calculation of 29Si NMR chemical shifts of various silicate species in the silicate solution as initial components for zeolite synthesis both in gas and solution phase. Calculations have been performed at geo...

full text

Ab Initio Calculations of P NMR Chemical Shielding Anisotropy Tensors in Phosphates: Variations Due to Ring Formation

Ring formation in phosphate systems is expected to influence both the magnitude and orientation of the phosphorus (P) nuclear magnetic resonance (NMR) chemical shielding anisotropy (CSA) tensor. Ab initio calculations of the P CSA tensor in both cyclic and acyclic phosphate clusters were performed as a function of the number of phosphate tetrahedral in the system. The calculation of the P CSA t...

full text

An ab initio quantum chemical investigation of TOMS nmr SHIELDING TENSORS IN Adenine-thymine, Adenine-uracil, Guanine-Cytosine & uracil-quartet: comparison between theoretical and experimental results

We have evaluated the NMR shielding tensors for A:T,G:C,A:U in Watson-crick, and U-quartet. We have computed NMR shielding tensors at B31YP level by using 6-31G(d) basis set. We have compute anisotropy and asymmetry in A:T,G:C,A:U and U-quartet. The NMR shielding tensors were calculated using the GIAO method. The natural bonding orbital analysis (NBO) were performed. NBO calculation have been ...

full text

NMR chemical shift data and ab initio shielding calculations: emerging tools for protein structure determination.

In this tutorial review, we discuss the utilization of chemical shift information as well as ab initio calculations of nuclear shieldings for protein structure determination. Both the empirical and computational aspects of the chemical shift are reviewed and the role of molecular dynamics and the accuracy of different computational methods are discussed. It is anticipated that incorporating the...

full text

Ab initio calculations of Co shielding in model complexes

Recent ab initio calculations of cobalt NMR shielding show that DFT-GIAO calculations using hybrid functionals are found to reproduce experimental values well. This method is used to calculate the variation of the cobalt NMR shielding tensor of sqaure pyramidal nitrosyl complexes with respect to the CoNO geometry and to differing basal ligands. The isotropic shielding is shown to have a large n...

full text

My Resources

Save resource for easier access later

Save to my library Already added to my library

{@ msg_add @}


Journal title

volume 2  issue 1

pages  9- 20

publication date 2005-05-01

By following a journal you will be notified via email when a new issue of this journal is published.

Hosted on Doprax cloud platform doprax.com

copyright © 2015-2023