Single-crystal neutron diffraction spectroscopy

Unfortunately, specialists in the field of single crystal NMR spectroscopy are not specialists in single crystal neutron diffraction, and, as with solid-state infrared spectroscopy, good experiments using both methods on the same crystalline compound are relatively rare, cf. [246, 247]. 

Single crystal neutron diffraction single crystal X-ray diffraction powder X-ray diffraction solid-state NMR spectroscopy... 

Single crystal neutron diffraction single crystal X-ray diffraction solid-state NMR analysis vibrational spectroscopy X-ray photoelectron spectroscopy Environmental (VT, VRH) XRPD VT SSNMR spectroscopy Raman/IR spectroscopy thermal analysis hot stage microscopy moisture sorption analysis slurry equilibration Moisture sorption analysis... 

Lam et al. (1974), Lander and Mueller (1974) and Lam and Aldred (1974) were the first to report on the properties of NpS. Their results are still valid. Comments on the unusual properties of NpS, especially the very low moments, are found in the work of Lander (1978) and Lam and Ellis (1985). The latter authors claim that hybridization and crystal-field interactions are responsible for the depression of the ordered moment. Single-crystal neutron diffraction and Mossbauer spectroscopy measurements refined the antiferromagnetic type II structure reported earlier for NpS (Blaise et al. 1992). The structure is of a multi-A type, most probably 2k. NpSe is... 

The structures of iron oxides have been determined principally by single crystal X-ray diffraction or neutron diffraction with supplementary information coming from infrared spectroscopy, electron diffraction and high resolution electron microscopy. A few years after the first successful application of X-ray diffraction to crystal structure determination, this technique was used to establish the major features of the structures of magnetite (Bragg, 1915 Nishikawa, 1915) and hematite (Bragg Bragg, 1918). 

Nitromethane, CH -NOf. The equilibrium structure of singlet nitromethane has been studied at several levels of theory [3,60,64-71]. Two conformations are possible for nitromethane, staggered (Is) and eclipsed (le), but the eclipsed form has been characterized as a transition structure at MP2/6-31G with an imaginary frequency of 30 cm 1 [3]. Rotation around the H3C-NO2 bond occurs essentially without barrier the estimated value is only 0.01 kcal/mol. This is in accordance with a microwave study, which reports a C-N rotation barrier of only 6 cal/mol [72,73]. The C-N bond length of nitromethane has been estimated with X-ray single crystal diffraction [74], neutron diffraction [46,75], microwave spectroscopy [72,73], MP2/6-31G [3], and B3LYP/6-31+G [71] at respectively 1.449, 1.486, 1.489, 1.485, and 1.491 A, showing that the theoretical estimates compare very well with those determined by experimental methods. The experimentally reported vibrational frequencies of nitromethane... 

The 13C-CP-MAS spectrum has also been used to complement the diffraction data relating to the crystal structure of cellulose, but hitherto the results have been inconclusive [242]. A significant amount of H single crystal spectroscopy has been reported and has been used as a basis for correlation with neutron diffraction data and with theoretical ab-initio molecular orbital calculations [243, 244]. 

Rutherford backscattering spectroscopy Scanning electron microscopy Secondary ion mass spectroscopy Single crystal X-ray diffraction Small angle X-ray and neutron scattering Spark source mass spectrometry Transmission electron microscopy Voltametry... 

Figure 2.9a shows the lipid molecule DMPC. Two layers contacted via the hydrophobic tails lead to spontaneous formation of a double-layer biomimetic membrane that can be transferred to a single-crystal ultraplanar electrochemical Au(lll) surface. The hydrophilic head groups contact the electrode surface via an intermediate water film. Due to the structurally very well-defined assembly, not only AFM and in situ STM but also neutron reflectivity. X-ray diffraction, and infrared reflection absorption spectroscopy (IRRAS) have been employed to support the direct visual in situ STM. Electrochemically controlled structural changes, phase transitions, and the effects of the common membrane component cholesterol (Figure 2.9b) and peptide drugs have been investigated in this way. 

In much of this book, we have been concerned with studying species that are soluble and subjected to solution techniques such as NMR and electronic spectroscopy, or with structural data obtained from X-ray or neutron diffraction studies of single crystals or electron diffraction studies of gases. The investigation of solid surfaces requires specialist techniques, many of which have been developed relatively recently. Selected examples are listed below. 

Stucki JW, Roth CB, Baitinger WE (1976) Analysis of iron-bearing clay minerals by electron spectroscopy from chemical analysis (ESCA). Clays Clay Minerals 24 289-292 Swope J (1997) Single crystal X-ray and neutron diffraction studies of the crystal chemical effects of OH=0 substitution in mantle ratile and of Cl-OH substitution in biotite, and the crystal chemistry of IM ferromagnesian trioctahedral micas. PhD dissertation, Dept Geological Sciences, University of Colorado, Botrlder, 85 p... 

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