Mixed phase hybridization

A somewhat related problem may occur when a crystal survives intact a phase transition upon loss of solvent gnest. These crystals may simultaneously contain domains characteristic of two distinct crystal phases and may be described as hybrid or composite crystals. As yet, there are no widely available programs that can refine such mixed-phase crystals. 

As shown, the mixing coefficients c, of the in-phase hybrid (4.25) must be switched with a sign change in the out-of-phase hybrid (4.26) to maintain mutual orthogonality. [For example, if hi is primarily of p-character (c > cj, then h2 is primarily of s-character and points in the opposite direction.] In HF (Fig. 4.1), the on-axis lone pair is the s-rich hybrid h2, whereas the two off-axis lone pairs are essentially the atomic p, py orbitals that were left uninvolved in bond formation. Thus, in linear bonding the off-axis (atom-hke)... 

Nylon-6. Nylon-6—clay nanometer composites using montmorillonite clay intercalated with 12-aminolauric acid have been produced (37,38). When mixed with S-caprolactam and polymerized at 100°C for 30 min, a nylon clay—hybrid (NCH) was produced. Transmission electron microscopy (tern) and x-ray diffraction of the NCH confirm both the intercalation and molecular level of mixing between the two phases. The benefits of such materials over ordinary nylon-6 or nonmolecularly mixed, clay-reinforced nylon-6 include increased heat distortion temperature, elastic modulus, tensile strength, and dynamic elastic modulus throughout the —150 to 250°C temperature range. 

Thermospray ionisation sources are usually outfitted with a quadrupole or magnetic sector mass spectrometer (including hybrids or tandem forms). Thermospray operation allows a reversed-phase solvent system, e.g. a 50 50 (v/v) water-methanol or acetonitrile mix containing 0.1 M ammonium acetate. This ensures compatibility with the universal HPLC procedures available in many industrial research laboratories. 

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