Journal of Physical & Theoretical Chemistry2120050501Response of semi-empirical and AB initio methods to angle strain and conjugation effects in (Z,Z,Z)-Cycloocta-1,3,5-triene376618ENIssaYavariNot-mentionedHassanKabiri-FardNot-mentionedJournal Article20150427The results of MNDO, AM1 and PM3 semi-empirical calculations and HF/6-31G*, MP/6-31G*, MP2/6-311+G**, and B3LYP/6-311G** and QCISD/6-31G* ab initio methods for angle strain and conjugation effects in twist-boat, boat, and half-chair geometries of (Z,Z,Z)-cycloocta-1,3,5-triene indicate that all methods, except PM3, predict wrong ordering of the conformations.https://jptc.srbiau.ac.ir/article_6618_00ee6682ca6494f014308f3662518e2f.pdfJournal of Physical & Theoretical Chemistry2120050501An Ab initio and chemical shielding tensors calculations for Nucleotide 5’-Monophosphates in the Gas phase9206619ENM.MonajemiNot-mentionedM.ASeyed SajjadiNot-mentionedR.SayyadiNot-mentionedG.GhassemiNot-mentionedJournal Article20150427Structural 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.https://jptc.srbiau.ac.ir/article_6619_e7eb868aeeb133a06603f09bd96474c6.pdfJournal of Physical & Theoretical Chemistry2120050501An ab initio quantum chemical investigation of TOMS nmr SHIELDING TENSORS IN Adenine-thymine, Adenine-uracil, Guanine-Cytosine & uracil-quartet: comparison between theoretical and experimental results21276620ENH.AghaieNot-mentionedM.MonajjemiNot-mentionedGh.GhassemiNot-mentionedM.KiaNot-mentionedJournal Article20150427We 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 done at B31LYP level. We have evaluated lowest occupancy orbitals, highest energy, donor and acceptor atoms, core and valence orbitals, total Lewis, natural population in atoms in NBO calculation.https://jptc.srbiau.ac.ir/article_6620_775fb058aef5555cdce7a16994fc74a0.pdfJournal of Physical & Theoretical Chemistry2120050501Ionic str4ength dependence of formation constants, complexation of Glycine with dioxouranium (VI) Ion29346621ENFarrokhGharibNot-mentionedAliShamelNot-mentionedFarbodLotfiNot-mentionedJournal Article20150427The dependence on ionic strength of protonation of glycine and its complexation with dioxouranium (VI) is reported in sodium perchlorate and sodium chloride solutions as background salts. The measurements have been performed at 25±0.1°C and various ionic strengths in the range 0.1 to 1.0 mol , using a combination of potentiometric and spectrophotometric techniques. The overall analysis of the present and the previous data dealing with the determination of stability constants at different ionic strengths allowed us to obtain a general equation, by which a formation constant determined at a fixed ionic strengths can be calculated, with a good approximation, at another ionic strength, if 0.1 ionic strength 1.0 mol sodium perchlorate or sodium chloride.https://jptc.srbiau.ac.ir/article_6621_80e3c5e03e00998dacd870f017594e10.pdfJournal of Physical & Theoretical Chemistry2120050501Thermodynamics of the solubility of potassium nitrate in the mixed solvent, Ethanol+Water, and the related Ion-association35396622ENM.AghaieNot-mentionedF.Ghaemi AmiriNot-mentionedM.GiahiNot-mentionedJournal Article20150427Using the evaporating method, the solubility of potassium Nitrate was determined in various mixtures containing Water and Ethanol at 25°C. The results show that the solubility of KNo3 decreases with increasing the mass percent of Ethanol in the mixtures. This trend is along with decreasing the dielectric constant of Water+Ethanol mixtures. Moreover, it can be concluded that the totqal solubility of KNO3 may be regarded as the sum of two contributions; one referring to the free ions in the solution and the other to K+NO3-ion-pairs which are formed in the saturated solution. Estimating the formation constant, KAm for the reaction K+(soln) + NO3-(soln) AK+NO3-
(ion-pair) , upon Bjerrum or fuoss models, then it is quite easy to evaluate the contributions of free ions and K+NO3-(ion-pair) to the total solubility.https://jptc.srbiau.ac.ir/article_6622_a4d3a942b4e026a9afdbb979e833a5a8.pdfJournal of Physical & Theoretical Chemistry2120050501Efficient one-pot synthesis and characterization of 13-Acetyl-9-methyl-11-oxo-8-oxa-10,12-diazatricyclo [7.3.1.0^2,7] trideca-2,4,6-triene41456623ENHojatollahSalehiNot-mentionedMohammadRabbaniNot-mentionedQian-RongLiNot-mentionedQing-xiangGuoNot-mentionedJournal Article20150427An efficient and environmentally friendly procedure for one-pot synthesis of 13-acetyl-9-methyl-11-ox-8-oxa-10,12-diazatricyclo [7.3.1. ] trideca-2,4,6-triene from salicylaldehyde, acetylaceton and urea via Biginelli condensation and intramolecular Michael-addition by using magnesium bromide as an expensive and easily available catalyst under solvent-free condition is desired. The structural elucidation of the product is also described by -and -NMR spectra and the detailed fragmentation routs of EI-TOFMShttps://jptc.srbiau.ac.ir/article_6623_d59973bb55e350a7b3680ca82a33e649.pdfJournal of Physical & Theoretical Chemistry2120050501The evaluation of basis set, method and initial geometry on structural properties of a cyclic phosphor amidate compound by SPSS47566624ENMajidMonajjemiNot-mentionedAnitaAbediNot-mentionedJournal Article20150427The structural properties of a new cyclic phosphor amide have been investigated in three methods and four basis sets and results have been compared with experimental data by spss. The best level for this type compound is HF/6-31++G** and with considering to this result, at this level, hyper chem input as initial geometry have been evaluated.https://jptc.srbiau.ac.ir/article_6624_2dd8a91281f907ea87c233be53589e54.pdf