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The hydrogen transfer reaction mechanism of the complex of a singlet thiol phosphinidene and a polar molecule hydrogen fluoride (HSP- - - HF) has been investigated at the B3LYP/6-311+G (d,p) level in order to better understand the reactivity of singlet phosphinidene. The results show that the relevant reaction, including step 1 [HSP- - -HF(1) → TS1 (2) → HSPH(F) (3)] and step 2 [HSPH(F) (3) → TS2 (4) → H2SPF (5)], are very different from the reactions of hydroxyl phosphinidene with hydrogen fluoride. Furthermore, theoretical studies on the thermodynamic and kinetic properties of the reaction have been carried out over the temperature range of 200–1200 K using the DFT/B3LYP method, the general statistical thermodynamics, and Eyring transition state theory with Wigner correction, which is used to examine the temperature effects the reaction channel. It is concluded that step 1 has both thermodynamic and kinetic advantages over step 2, and the high temperature is favorable to step 2. Moreover, the order of l...

The insertion reactions of singlet aluminium monohalides 1(AlX) (X = F, Cl, Br) with hydrogen halides (HX) have been investigated by the DFT/B3LYP method at the B3LYP/6-311 + G( d, p) level, which involve three-membered ring transition states (TS). In addition, general statistical thermodynamics and Eyring transition state theory with the Wigner correction were used to study the thermodynamic and kinetic properties of these reaction channels within the temperature range of 200-1200 K. It is concluded that with increasing temperature, the reaction equilibrium constant K decreases sharply, while the reaction rate constant k increases gradually for all these insertion reactions. The orders are K(F) > K(Cl) > K(Br) and k(Br) > k(Cl) > k(F) over the entire temperature range of 200-1200 K, while the differences of lg K and lg k at low temperature are larger than those at high temperature.

Theoretical studies on the thermodynamic and kinetic properties of the reactions of Ti+ with sulfur transfer reagent SCO via the C═S bond activation pathway have been carried on using DFT/B3LYP method, general statistical thermodynamics, and Eyring transition state theory with Wigner correction. The relevant reactions include reaction 1 4 Ti++1SCO → 4 IM 1 → 4 TS 1 → 4 IM 2 → 4 TiS++ 1 CO, and reaction 2 4Ti++1SCO →4IM1→ CP →2IM2→2TiS++1CO in which the spin multiplicity changes from the quartet state to the doublet state in the crossing region. It is concluded that the increase of the temperature is favored to the reaction 1 process, since the equilibrium constants (K) rises from 0.566 × 10[P]-9 at 200 K to 0.109 × 100 at 1200 K, and the reaction rate constant (k) from 0.222 × 100 s[P]-1 at 200 K to 0.540 × 10 11 s[P]-1 at 1200 K. Moreover, reaction 1 is endothermic, and non-spontaneous in the way the entropy increases, while reaction 2 is exothermic and spontaneous in the way their entropy decreases. The...

The two-dimensional coordination polymer cadmium phosphate with the morphology of rectangle layers was prepared by solid-state template reaction at room temperature, and was characterized by XRD, FTIR, and TEM techniques. The as-synthesized sample is a layered cadmium phosphate material, in which the structure is poly (CdPO4−) anion framework with ammonium ions and water species residing in the space between the layers, and cadmium ions are coordinated by the phosphate oxygen atoms. This article also presents the adsorption of Pb(II) ions from aqueous solution on the as-synthesized coordination polymer cadmium phosphate, and the results showed that this inorganic polymer adsorbent had good adsorption capacity. It could reach to the saturation adsorption capacity within an hour, and its excellent adsorption capacity for Pb(II) was 5.50 mmol/g when the initial solution concentration was 1.68 × 103 μg/mL at T = 278K. Moreover, the adsorption kinetics and adsorption isotherms were studied, it revealed that the adsorption kinetics can be modeled by pseudo second-order rate equation wonderfully. The apparent activation energy (Ea), ΔG, ΔH, and ΔS were 3.16 kJ mol−1, −13.97 kJ mol−1, −11.84 kJ mol−1, and 7.66 J mol−1 K−1, respectively. And it was found that Langmuir equation could well interpret the adsorption of the as-synthesized coordination polymer cadmium phosphate for Pb(II) ions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Theoretical studies on the thermodynamic and kinetic properties of the reactions of scandium (I) ion with the sulfur-transfer reagent SCO via the C-O bond activation pathway have been carried out over the temperature range of 200-1200 K using the DFT/B3LYP method, general statistical thermodynamics, and Eyring transition state theory with Wigner correction. The relevant reactions include reaction 1 1Sc+ + SCO → 1IM1 → 1TS1 → 1IM2 (Step 1) → 1TS2 → 1IM3 → 1ScO+ + 1CS (Step 2), and reaction 2 3Sc+ + SCO → 3IM1 → CP → 1IM2 → 1TS2 → 1IM3 → 1ScO+ +1CS in which the spin multiplicity changes from the triplet state to the singlet state in the crossing region. It was concluded that the order of the equilibrium constants (K) and the reaction rate constants (k) are consistent with that of their corresponding exoergic energies, ΔE, and reaction barriers, respectively. Step 2 of reaction 1 is both thermodynamically and kinetically favored over the whole temperature range. Moreover, both Reaction 1 and reaction 2 are exothermic and spontaneous processes in which their entropy increases, and the magnitudes of their thermodynamic values all decrease with increasing temperature.

Cadmium phosphate with rectangle layers morphology has been synthesized by a convenient method of solid-state template reaction at room temperature, and was characterized by several methods. The sample cadmium phosphate showed the average length/width of the layers within the range of 0.8–1.5 μm, and it had a strong fluorescence emission peak centered at 306 nm. Moreover, we also studied its absorption properties for Hg(II) and Ag(I) ions, and found that its excellent absorption capacity for Hg(II) and Ag(I) could reach to 3.14 and 2.96 mmol g −1 , and its absorption ratio was 92.7% and 84.4%, respectively, at pH 5.98, T = 15 °C and the absorption time t = 24 h.