The use of the MP2 aproximation with a small basis set is known to reproduce interaction energies for weakly bonded complexes with fairly good accuracy, when corrected for the BSSE. However, it is always a good practice to compare the results obtained in this fashion with higher-level calculations whenever they are computationally allowable. In the case of the BTT-aminoacid complexes studied in...

Post-Hartree-Fock ab initio quantum chemical calculations were performed for 5-fluorouracil in the gas phase and in a three-water cluster. Full geometry optimizations of the 5-fluorouracil-water complexes were carried out at the MP2/6-31+G(d,p) level of theory. MP4/6-31+G(d,p)//MP2/6-31+G(d,p) and MP4/6-31++G(d,p)//MP2/6-31+G(d,p) single-point calculations were performed to obtain more accurate...

The quantum Monte Carlo (QMC) technique is used to generate accurate energy benchmarks for methane-water clusters containing a single methane monomer and up to 20 water monomers. The benchmarks for each type of cluster are computed for a set of geometries drawn from molecular dynamics simulations. The accuracy of QMC is expected to be comparable with that of coupled-cluster calculations, and th...

Electronic structure theory such as ab initio molecular orbital (MO) theory is the powerful tool in elucidating chemical phenomena such as electronic states, molecular structures, properties, and reaction mechanisms. The high-level quantum chemical calculations excellently reproduce the properties for small molecules in the same or better accuracy with the experiments. However, the computationa...

In this paper, correlated studies on a test set of 36 small molecules are carried out with both wavefunction (HF, MP2, CCSD) and density functional (LDA, KT3, cTPSS, cM06-L) methods. The effect correlation exotic response properties such as molecular electronic anapole susceptibilities is studied the performance various approximations benchmarked against CCSD and/or MP2. Atoms traditionally cla...

Relative populations of three energy-lowest IPR (isolated-pentagon-rule) isomers Eu@C 88 are computed using the Gibbs energy based on characteristics from density functional theory and MP2 calculations (M06-2X/3-21G∼SDD entropy term, MP2=FU/6-31G*∼SDD or B2PLYPD=FU/6-31 + G*∼SDD energetics). The predict coexistence isomers, in agreement with extraction a polar solvent, offer possible explanatio...

Calmodulin-dependent myosin light chain kinase phosphorylates two light chain subunits on each myosin molecule. We have developed a method for measuring nonphosphorylated, monophosphorylated, and diphosphorylated forms of myosin in smooth muscle. Four protein bands were separated in tissue extracts by nondenaturing polyacrylamide gel electrophoresis in the presence of pyrophosphate. Immunoblots...

The addition of sodium acetate to chemically defined MP2 medium was found to increase and stabilize solvent production and also increase glucose utilization by Clostridium beijerinckii NCIMB 8052. RNA and enzyme analyses indicated that coenzyme A (CoA) transferase was highly expressed and has higher activity in C. beijerinckii NCIMB 8052 grown in MP2 medium containing added sodium acetate than ...

Complete basis set limit calculations are carried out for the fcc lattices of solid neon and argon, using secondto fourth-order Møller-Plesset theory, MP2–MP4, and coupled-cluster calculations, CCSD T , to describe electron correlation within a many-body expansion of the interaction potential up to third order. A correct description of the three-body Axilrod-Teller-Muto term for the solid state...