内行
发表于 2025-3-23 11:31:57
1H NMR Spectroscopy,In long-chain alkanes, the methyl groups at δ ca. 0.8 ppm typically show distorted triplets due to second-order effects.
nonplus
发表于 2025-3-23 15:28:32
Heteronuclear NMR Spectroscopy,To estimate the .F chemical shifts of substituted 6-ring heteroaromatics, the same increments, Z., can be used as for substituted fluorobenzenes (see preceding page). However, different base values, Y (as given below), apply depending on the number and position of nitrogens and the position of the fluorine substituent in question.
agglomerate
发表于 2025-3-23 19:17:30
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inflame
发表于 2025-3-23 22:19:40
Mass Spectrometry,. Larger alkyl fragments (with C.) are chiefly formed by direct cleavage. They dehydrogenate and undergo substantial H and skeleton rearrangements. Smaller alkyl fragments (C. to C.) are mainly formed by secondary decomposition of higher alkyl fragments. Eliminations of groups from within the chain (and recombination of its ends) also occur.
NATAL
发表于 2025-3-24 06:12:42
UV/Vis Spectroscopy,The π→π. transition of conjugated double bonds is above ≈200 nm with typical intensities of the order of log ε ≈ 4. Its position can be estimated with the Woodward–Fieser rule. For cross-conjugated systems, the value for the chromophore absorbing at the longest wavelength has to be calculated.
施舍
发表于 2025-3-24 09:09:39
Martin Badertscher,Philippe Bühlmann,Ernö PretschFourth edition of the highly successful textbook now offering 20% new data.Now included are chapters on (19)F-NMR and (31)P-NMR as well as references to important Raman bands.Includes supplementary ma
Antigen
发表于 2025-3-24 13:18:07
Ernö Pretsch,Philippe Bühlmann,Martin Badertschertry and solid-state physics. The book by Fulde presented the problem of electron correlations in molecules and solids in a unified form. The common feature of these fields is also the use of the LCAO (linear combination of atomic orbitals) approximation: being from the very beginning the fundamental
虚构的东西
发表于 2025-3-24 16:56:03
Ernö Pretsch,Philippe Bühlmann,Martin Badertscherquantum chemistry is to calculate the properties of molecules and crystals without the use of empirical parameters. In principle, all the particles-electrons and nuclei-should be involved in such calculations. In fact, the solution of this complicated task is simplified in the Born-Oppenheimer appro
初学者
发表于 2025-3-24 19:51:16
Ernö Pretsch,Philippe Bühlmann,Martin Badertscherructure. However, real solids do not demonstrate translational symmetry. Boundaries and other regions of disruption of translational symmetry called defects are always present. Many practical applications of solids are based on the use of the properties caused by defects. By varying the defect struc
改革运动
发表于 2025-3-25 00:54:10
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