Search results
Results from the WOW.Com Content Network
The chair conformation is the most stable conformer. At 298 K (25 °C), 99.99% of all molecules in a cyclohexane solution adopt this conformation. The C–C ring of the chair conformation has the same shape as the 6-membered rings in the diamond cubic lattice. [7]: 16 This can be modeled as follows.
A methyl substituent has a significantly smaller A-value than a tert-butyl substituent; therefore the most stable conformation has the tert-butyl in the equatorial position. The utility of A-values can be generalized for use outside of cyclohexane conformations. A-values can help predict the steric effect of a substituent. In general, the ...
The two have equal free energy; neither is more stable, so neither predominates compared to the other. A negative difference in free energy means that a conformer interconverts to a thermodynamically more stable conformation, thus the equilibrium constant will always be greater than 1.
A fuel cell is an electrochemical energy conversion device. Fuel cells differ from batteries in that they are designed for continuous replenishment of the reactants consumed. This is a partial list of companies currently producing commercially available fuel cell systems for use in residential, commercial, or industrial settings.
The conformation which places the methyl group in the equatorial position is 3.16 kcal/mol more stable than the axial conformation. [7] The product ratio of 95:5 indicates that the more stable conformer leads to the major product. [8]
MM, DFT, semiempirical methods, parallel MD, conformational analysis, Linear scaling SCF, docking protein-ligand, Batch processing, virtual screening, automated builders (molecular dynamics, proteins, crystals) Proprietary: SCIGRESS.com: Spartan: Yes Yes Yes No Yes No Yes Yes No
More complex molecules, such as butane, have more than one possible staggered conformation. The anti conformation of butane is approximately 0.9 kcal mol −1 (3.8 kJ mol −1) more stable than the gauche conformation. [1] Both of these staggered conformations are much more stable than the eclipsed conformations.
Generally, axial pumps tend to give much lower pressures than centrifugal pumps, and a few bars is not uncommon. Their advantage is a much higher volumetric flowrate. For this reason they are common for pumping liquid hydrogen in rocket engines, because of its much lower density than other propellants which usually use centrifugal pump designs.