Super-molecule

Table 5 Intra- and inter-pair correlation energy contributions for the localized molecular orbitals in the super-molecule + H2O...

The procedure for obtaining SMOs starts from the occupied and virtual canonical molecular orbitals (CMOs) of the super-system it uses a bridge in order to transform the CMOs towards a prescribed set of orbitals. The criterion prescribes, that the overlap between the constmcted orbitals tj/ of a super molecule (SM) should be maximal with the initial, canonical orbitals (j) of the non-interacting molecules, the bridge thus implies an overlap criterion ... 

Orbital No. CMOs in super-molecule CMOs in monomers CMOs in super-molecule... 

That study at the MP2 correlated level for the dimers investigated are summarized in Table 7. In Table 7, we use the following notations SM denotes the values obtained in the super-molecule, while CP denotes those obtained in the counter-poise corrected calculations. The results clearly show, that the E(intra/net) values are close to each other (using any basis sets) for the monomers in both of SM and CP systems. This suggests that the SMO-LMBPT scheme takes into account the benefit effect of the basis set superposition. The deviations found in the intra terms between the SM and CP systems are explained recently (Kapuy etal, 1998) in detail. 

The formation of a complex Species by the association of two or more chemical entities (having, in general, electronic closed shells) is one of the most fundamental molecular processes in biology, in chemistry and in physics. Such a super-molecule represents the next higher level of physical complexity after the nucleus, the atom and the molecule. Its formation involves bonding interactions which are much weaker than the usual well defined covalent bonds. 

Optimal disposition of primary and secondary catalytic groups within a single super molecule or on a polymer or membrane template according to its sterical adjusting for attacking substrates. 

Molecules consist of atoms which have a certain mass and which are connected by elastic bonds. As a result, they can perform periodic motions, they have vibrational deitrees of freedom All motions of the atoms in a molecule relative to each other are a superposition of so-called normal vibrations, in which all atoms are vibrating with the same phase and normal frequency. Their amplitudes are described by a normal coordinate. Polyatomic molecules with n atoms possess 3n - 6 normal vibrations (linear ones have 3n - 5 normal vibrations), which define their vibrational spectra. These spectra depend on the masses of the atoms, their geometrical arrangement, and the strength of their chemical bonds. Molecular aggregates such as crystals or complexes behave like super molecules in which the vibrations of the individual components are coupled. In a first approximation the normal vibrations are not coupled, they do not interact. However, the elasticity of bonds does not strictly follow Hooke s law. Therefore overtones and combinations of normal vibrations appear. 

The Co Q cluster was investigated using the same -super-molecule model as was used for Co. With ten d" atoms, the optimal cluster can be described as two pyrcunids in their lowest quartet states bound together by their square bases. Hence, a triple-bonded species (one cT bond and two bonds )... 

Figure 6.1 shows the structure of the flagellar motor in a simple illustration that reminds us of artificial machines. This machine-like motor is constructed through the self-assembly of proteins. The superior fimctionality and complexity of biological super molecules is quite apparent from this example. The energy for the rotation of the motor is provided by a proton flow from the outside to the inside of the bacteria. When an electrical potential difference is applied between the outside and the inside of the bacteria by immobilizing the bacterial cell on micropipette, the rotation speed can be controlled by al-... 

The first ab initio calculations on interaction dipoles were performed by Matcha and Nesbet They considered the systems HeNe, HeAr and NeAr as super-molecules and did ordinary Hartree-Fock-LCAO-SCF calculations in the range R = 2.0 to 5.5aQ. Because of the Hartree-Fock approximation they did not obtain the dispersion contribution to the dipole moment (cf. sect. 2), but only exchange, penetration and overlap-induction contributions. Their ab initio dipoles could be fitted quite well by a single exponential, which supported the assumption made earlier by Van Kranendonk ... 

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