Alternative configuration

Configuration selection is have we found among all the alternative configurations the one that best satisfies our objectives Is there something about a composite structure that involves different freedoms... 

Qualitative or quantitative mass spectrometric analysis can be made by one of two alternative configurations. Either the sample is decomposed in the high vacuum chamber of the mass spectrometer (MS) itself or reaction proceeds in an external system at higher pressure (e.g. a microbalance)... 

Figure 21. A low-energy portion of the energy level structure of a tunneling center is shown. Here e < 0, which means that the reference, liquid, state structure is higher in energy than the alternative configuration available to this local region. A transition to the latter configuration may be accompanied by a distortion of the domain wall, as reflected by the band of higher energy states, denoted as ripplon states.

In conformity with Hund s rule, a metal complex with the configuration / 2 g Sg has four unpaired electrons. This configuration maximizes the number of electrons with unpaired spins, so it is described as high-spin. The alternative configuration, t2 g Sg, has just two unpaired electrons and is described as low-spin. 

It has been shown that photoexcitation of the guanine-cytosine (G-C) base pair leads to proton transfer [231], Watson-Crick (WC) base pairs have excited state lifetimes much shorter than other non-WC base pairs indicating once again that the natural occurring WC base pairs are more photostable than other alternative configurations [115, 118, 232-235], Much work has been done in the gas phase where many different base pair isomers exist. The ultrafast relaxation of the WC base pair has also been confirmed in solution using fluorescence up-conversion measurements [117]. 

Seebach, D., Sifferlen, T., Mathieu, P. A., Hane, A. M., Krell, C. M., Bierbaum, D. J., and Abele, S. (2000). CD spectra in methanol of /3-oligopeptides consisting of /3-amino acids with functionalized side chains, with alternating configuration, and with geminal backbone substituents. Fingerprints of new secondary structures Helv. Chim. Acta 83, 2849-2864. 

The relations indicated by these two equations are shown graphically in Figure 8.12 for two alternative configurations. In both cases the cascade operates between the same initial and... 

In the earlier study of Chang and Chadi (1988), an alternative configuration was identified where the Si and P atoms moved apart slightly. This was subsequently identified as a metastable configuration (Denteneer et al., 1990 Zhang and Chadi, 1990). 

These cells have been designed for a great number of alternative configurations, including ... 

A catalytic membrane reactor (CMR) presents an alternate configuration where the membrane is both catalytically active and permselective. The reactant conver-... 

Hz, H6) and 6.22 (IH, s, H7). Examination of a model of 300 shows a dihedral angle of about 110° for H(5)—CC—H(6), thus explaining the observed doublets. For the alternative configuration of the ozonide moiety, with O, on the a-phase, this angle would be nearly orthogonal and the coupling constant would be nearly nil . ... 

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