A sensitivity-enhanced IPAP NMR experiment was described in this paper, whichseparates the ~1H-^(15)N doublets into two different spectra to alleviate the problem of resonanceoverlaps and achieve the accurate measurem...A sensitivity-enhanced IPAP NMR experiment was described in this paper, whichseparates the ~1H-^(15)N doublets into two different spectra to alleviate the problem of resonanceoverlaps and achieve the accurate measurement of J and residual dipolar coupling constants inproteins. This experiment offered 20%―60% sensitivity enhancement over the original IPAPexperiment, and therefore produced more measurable resonances. Pulsed field gradient was used forcoherence selection. Water-flip-back approach was used for water suppression. Thesensitivity-enhanced IPAP experiment was employed in the measurement of ~1J_(NH) and ~1D_(NH)constants of the protein UBC9.展开更多
The spin crossover（SCO） compound [Fe（bapbpy）（NCS）2],where bapbpy contains two fused N,N-bis（2-pyridyl）amines,has been studied by DFT/TD-DFT/BS-DFT methods.Several density functionals and basis sets were used i...The spin crossover（SCO） compound [Fe（bapbpy）（NCS）2],where bapbpy contains two fused N,N-bis（2-pyridyl）amines,has been studied by DFT/TD-DFT/BS-DFT methods.Several density functionals and basis sets were used in the calculation to obtain optimized geometries of the compound in the low-（LS） and high-spin（HS） states.The vibrational modes and IR spectra,spin splitting energies,excited states and UV/Vis absorption spectra were obtained.The structural parameters of the calculated isolated complex are in good agreement with the X-ray data.We investigate three dimers of [Fe（bapbpy）（NCS）2] complex for their magnetic properties.It has been found that the complex（1,3） has ferromagnetic character while the others are antiferromagnetic in nature by using a broken symmetry approach in the DFT framework（BS-DFT） with support from the coupling constant values（J） and spin density plots.展开更多
文摘A sensitivity-enhanced IPAP NMR experiment was described in this paper, whichseparates the ~1H-^(15)N doublets into two different spectra to alleviate the problem of resonanceoverlaps and achieve the accurate measurement of J and residual dipolar coupling constants inproteins. This experiment offered 20%―60% sensitivity enhancement over the original IPAPexperiment, and therefore produced more measurable resonances. Pulsed field gradient was used forcoherence selection. Water-flip-back approach was used for water suppression. Thesensitivity-enhanced IPAP experiment was employed in the measurement of ~1J_(NH) and ~1D_(NH)constants of the protein UBC9.
基金Supported by the Natural Science Foundation of Shandong Province(No.Y2006B43)
文摘The spin crossover（SCO） compound [Fe（bapbpy）（NCS）2],where bapbpy contains two fused N,N-bis（2-pyridyl）amines,has been studied by DFT/TD-DFT/BS-DFT methods.Several density functionals and basis sets were used in the calculation to obtain optimized geometries of the compound in the low-（LS） and high-spin（HS） states.The vibrational modes and IR spectra,spin splitting energies,excited states and UV/Vis absorption spectra were obtained.The structural parameters of the calculated isolated complex are in good agreement with the X-ray data.We investigate three dimers of [Fe（bapbpy）（NCS）2] complex for their magnetic properties.It has been found that the complex（1,3） has ferromagnetic character while the others are antiferromagnetic in nature by using a broken symmetry approach in the DFT framework（BS-DFT） with support from the coupling constant values（J） and spin density plots.
