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Oxygen atom sets

Take note of Dunning s notation. He writes the primitives (10s6p) and the contracted basis functions in square brackets [5s3p]. To give a detailed example, consider the oxygen atom set in Table 9.7. [Pg.169]

Atomic weight the weight of an atom compared with the weight of an oxygen atom set at 16. [Pg.2]

Consider the three atomic ic orbitals in the ozone molecule itA, itB, nc, where A is the central oxygen atom. Set up the VB wave functions corresponding to the three valence structures ... [Pg.194]

Once the atoms arc defined, the bonds between them arc specified in a bond block. Each line of this block specifies which two atoms are bonded, the multiplicity of the bond (the bond type entry) and the stereo configuration of the bond (there arc also three additional fields that arc unused in Molfiles and usually set to 0). The indices of the atoms reflect the order of their appearance in the atom block. In the example analyzed, V relates to the first carbon atom (see also Figure 2-24). "2" to the second one, 3" to oxygen atom, etc. Then the two first lines of the bond block of the analyzed file (Figure 2-29) describe the single bond between the two carbon atoms C1-C2 and the double bond C2=0-5, respectively. [Pg.50]

Figure 13.5 A Mg + atom links GTP to the Ras protein. Mg Is coordinated to one oxygen atom each from the p and y phosphates of GTP as well as to the side chains of Set 17 and Thr 35 of Ras. Two water molecules complete the octahedral coordination of Mg. Figure 13.5 A Mg + atom links GTP to the Ras protein. Mg Is coordinated to one oxygen atom each from the p and y phosphates of GTP as well as to the side chains of Set 17 and Thr 35 of Ras. Two water molecules complete the octahedral coordination of Mg.
Optimize the structure of acetyl radical using the 6-31G(d) basis set at the HF, MP2, B3LYP and QCISD levels of theory. We chose to perform an Opt Freq calculation at the Flartree-Fock level in order to produce initial force constants for the later optimizations (retrieved from the checkpoint file via OptsReadFC). Compare the predicted spin polarizations (listed as part of the population analysis output) for the carbon and oxygen atoms for the various methods to one another and to the experimental values of 0.7 for the C2 carbon atom and 0.2 for the oxygen atom. Note that for the MP2 and QCISD calculations you will need to include the keyword Density=Current in the job s route section, which specifies that the population analysis be performed using the electron density computed by the current theoretical method (the default is to use the Hartree-Fock density). [Pg.130]

From intermediate 43, the path to monensin would seemingly be straightforward. A significant task which would remain would be the construction of the l,6-dioxaspiro[4.5]decane substructure of monensin. You will note that the oxygen atoms affixed to carbons 5 and 12 in 43 reside in proximity to the ketone carbonyl at C-9. In such a favorable setting, it is conceivable that the action of acid on 43 could induce cleavage of both triethylsilyl ethers to give a keto triol which could then participate in a spontaneous, thermodynamically controlled spiroketalization reaction. Saponification of the C-l methyl ester would then complete the synthesis of monensin. [Pg.233]

The goodness of the PP representation can be checked by comparing the all-electron and PP orbital energies and relative stability of atomic states. The comparison is shown in Table 4, and is seen to be very satisfying. For a balanced treatment, also the carbon and oxygen atoms were treated by a PP, as described in previous work5.3d functions were not introduced in the sulphur basis set, mainly because they were not deemed necessary for the illustrative purposes of this chapter. Also, the derivation of a PP representation for polarization functions is not a straightforward matter. The next section is devoted to the discussion of this point. [Pg.17]

The suggested structure places eight titanium atoms and two groups of eight oxygen atoms each in the positions 8c, with three sets of... [Pg.494]

Recognizing the impracticability of determining the positions of the oxygen atoms from X-ray data, we have predicted a set of values for the oxygen parameters with the use of assumed minimum interatomic distances which is found to account satisfactorily for tbe observed intensities of a large number of reflections and which also leads to a structure which is physically reasonable. [Pg.534]

In this study, set up the parameters to analyze the dynamics of the oxygen atoms in the atmosphere based on the above data. Use a 50 x 50 = 2500 cell grid and start with all the cells in the excited S state. Let A = the S state, B = the state, and C = the ground state. Start with all of the ingredients in the excited state. To convert from Okabe s rate constants, given in units of s , to probabilities per iteration, divide the above values by 10 so that 10 iterations... [Pg.155]


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See also in sourсe #XX -- [ Pg.19 ]




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Oxygen atom

Oxygen atomic

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