Complex water

Blue manganese lV) fluoride, Mnp4 (Mn plus Fj), is immediately hydrolysed by water complex hexafluoromanganales containing [MnF j] " ions are yellow (electrolytic oxidation of lower fluorides or use of BrFs). [Pg.250]

Prepa.ra.tlon, There are several methods described in the Hterature using various cobalt catalysts to prepare syndiotactic polybutadiene (29—41). Many of these methods have been experimentally verified others, for example, soluble organoaluminum compounds with cobalt compounds, are difficult to reproduce (30). A cobalt compound coupled with triphenylphosphine aluminum alkyls water complex was reported byJapan Synthetic Rubber Co., Ltd. (fSR) to give a low melting point (T = 75-90° C), low crystallinity (20—30%) syndiotactic polybutadiene (32). This polymer is commercially available. [Pg.530]

Ultraviolet spectroscopy metal in water complexes, 2, 309 redox potentials and, 1,498 Ultraviolet-visible spectroscopy, 1, 243 Umbellicomplexone metallofluorescent indicator, 1. 558 Undecametallic complexes, 1, 167 Uni thiol chelating agent heavy metal poisoning, 6. 767 Unsaturated compounds hydrogenation... [Pg.241]

The water complexes are high spin, whereas the cyanide and phen complexes are low spin. In the case of the cyanide and phen complexes, the interconversion of the 2g iron(ii) and /2g iron(iii) states simply involves the loss or gain of an electron from the 2g level. Since these are the orbitals oriented between the ligand donor atoms. [Pg.192]

Sukrat, K. and Parasuk, V. (2007) Importance of hydrogen bonds to stabilities of copper-water complexes. Chemical Physics Letters, 447, 58-64. [Pg.235]

A protein-surfactant-water complex forms in the solid phase. Upon adsorption of a certain number of surfactant molecules, the complex s hydrophobicity increases, driving its transport into the liquid phase. [Pg.476]

B. Segregation Crystallisation, differentiation and accumulation Bushveld chromite still water complex Sukinda chromite... [Pg.43]

Following the transition state 6TS2 downhill, we end up with the cationic iron water complex 63, which is found -70 or -67 kcal/mol more stable than the reactants at the CCSD(T) or CASPT2 levels, respectively. The B3LYP numbers are similar, yielding -73... [Pg.274]

He Y, Wu C, Kong W (2004) Photophysics of methyl-substituted uracils and thymines and their water complexes in the gas phase. J Phys Chem A 108 943... [Pg.331]

Marian CM, Schneidaer F, Kleinschmidt M, Tatchen J (2002) Electronic excitation and singlet-triplet coupling in uracil tatutomers and uracil-water complexes. Eur Phys J D 20 357... [Pg.333]

Yoshikawa A, Matsika S (2008) Excited electronic states and photophysics of uracil-water complexes. Chem Phys 347 393 104... [Pg.337]

The rate maximum at pH 4 is assigned to a specific reaction of the monoester anion 104 which exists exclusively under these conditions. Westheimer 57) first advanced a metaphosphate ion mechanism in which 102 is formed via a six-membered monoester-anion/water complex (103). An intramolecular proton transfer via a four-membered ring according to 105 m is also conceivable, as is the formation of a zwitterion 106 in a prior protonation equilibrium. [Pg.94]

Han and Suhai126 reported the DFT(Yct), DFT(S/LYP), DFT(SVWN), DFT(B3LYP), and DFT(BLYP) calculations on N-methylacatemide-water complex. The N-methyla-catemide molecule may be considered one of the simplest models of the main chain of proteins. Conformational equilibria of clusters of N-methylacatemide and from one to three water molecules were studied using the DFT(B88/null), DFT(Ya), DFT(S/LYP), DFT(SVWN), DFT(B3LYP), and DFT(BLYP) calculations. The DFT(B3LYP) results compared most favorably with the ones steming from the MP2 calculations. [Pg.102]

Han, W.-G., and S. Suhai. 1996. Density Functional Studies on N-Methylacatemide-Water Complex. J. Phys. Chem. 100, 3942. [Pg.126]

The final ingredient that enters the calculation is the density factor pw. This is the actual density of water appropriate to the thermodynamic state intended in the calculation. For the usual case of 1 atm. pressure and 298K, this is I gem 3. The reference density in the electronic structure calculations is p° = 1 atm//entropic cost of sequestering water in the metal-water complexes, the free energies should be adjusted by —mRT In (pi 2o/p ) = —mRTIn (1354). With these inputs the excess chemical potential is readily composed as per (9.50), provided the optimal value of m is known. This is found by composing the excess chemical potential for different assumed m values and identifying the most stable case. For the dication transition metals studied, this is found to be six, consistent with experiment [12]. [Pg.340]

Radon difluoride is quantitatively reduced to elemental radon by water in a reaction which is analogous to the reactions of krypton difluoride and xenon difluoride with water. Complex salts of radon also hydrolyze in this fashion. [Pg.246]

Figure 5.6 Correlated variations of energetic (AE0...h), geometrical (Ro-e and Ai AH), and vibrational (Avah) properties of H-bonded water complexes (H20- -HA, A = F [crosses], OF [circles], NH2 [triangles], and CH3 [squares] with respect to donor-acceptor interaction AEn(Jd2) (abscissa, 1 kcalmol 1 tick marks). Vertical tick marks in each panel correspond to the quantity being plotted (a) AAo-h, 1 kcalmol 1 (b) Ro-e, 0.1 A (c) A Ah, 0.001 A and (d) Avah, 100 cm 1. (See Table 5.7 for numerical values.)...

Table 5.8. The NBO descriptors ofH-bonded water complexes E O- -HA, showing the net intermodular charge transfer from Lewis base to Lewis acid (Qcr), change in covalent-bond polarity ( Az ah). and (P)NBO overlaps (Sno, SniJ) of n0 with antibond ctah and ctah orbitals...

A novel form of Y HX hydrogen bonding49 results when the Lewis base Y is itself a hydride ion (H-). Because the electron affinity of a hydrogen atom is extremely weak (21 kcal mol-1), the H- ion is among the most weakly bound and diffuse anionic species known, and hence a powerful Lewis base. In this case, the H - -HX complex can be referred to as a dihydrogen bond 50 to denote the unusual H-bonding between hydrogen atoms. A water complex of this type was... [Pg.624]

Fig. 15. Correlation between hydrogen bond strength and iGluRl/2 vs 3/4 selectivity among willardiines. Unsubstituted/alkylated willardiines and azawillardiines lie in one series, halo-genated derivatives in another. The strength of anion-water complex is calculated as E[ArO(-)] + E[H20] - E[ArO(-)...HOH] at B3LYP/6-311+G(d,p).

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