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New scaling factors have been determined for obtaining fundamental vibrational frequencies and zero-point vibrational energies from harmonic frequencies calculated at the HF/6-3l G* and MP2/6-3l G* levels. The scaling factors for the fundamental frequencies have been derived from a comparison of a total of 1066 calculated frequencies for 122 molecules with corresponding experimental values, while the zero-point energy scaling factors were determined from a comparison of the computed values with the experimental zero-point energies for a set of 24 molecules. The scaling factors recommended are, respectively, 0.8929 and 0.9427 for HF/6-3IG* and MP2/6-31G* fundamental frequencies, and 0.9135 and 0.9646 for HF/6-31G* and MP2I6-31G* zero-point energies. RMS errors were determined to be around 50 cnr? for the HF and MP2 fundamental frequencies, and around 0.4 kJ mol" for the HF and MP2 zero-point energies.

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The reversibility of metal anode is af undamental challenge to the lifetime of rechargeable batteries.T hough being widely employed in aqueous energy storage systems, metallic zinc suffers from dendrite formation that severely hinders its applications.H ere we report texturing Zn as an effective way to address the issue of zinc dendrite.Anin-plane oriented Zn texture with preferentially exposed (002) basal plane is demonstrated via as ulfonate anion-induced electrodeposition, noting no solid report on (002) textured Zn till now. Anion-induced reconstruction of zinc coordination is revealed to be responsible for the texture formation. Benchmarking against its (101) textured-counterpart by the conventional sulphate-based electrolyte,the Zn (002) texture enables highly reversible stripping/plating at ah igh current density of 10 mA cm À2 ,s howing its dendrite-free characteristics.T he Zn (002) texture-based aqueous zinc battery exhibits excellent cycling stability.T he developed anion texturing approach provides ap athwayt owards exploring zinc chemistry and prospering aqueous rechargeable batteries.

Ab initio molecular orbital calculations at a variety of levels of theory have been carried out for a number of prototypical radical addition reactions with a view to determining a level of theory suitable for predicting reliable barriers. Closest agreement with experimental barriers is achieved with a variant of the recently introduced CBS-RAD procedure. At this level, the mean absolute deviation from experimental barriers for methyl radical additions in solution is just 1.4 kJ mol-1. A second high-level theoretical procedure examined is a variant of G2(MP2,SVP), corresponding effectively to QCISD(T)6-311+G(3df,2p) energy calculations on QCISD/6-31G(d) optimized geometries and incorporating scaled B3-LYP/6-31G(d) zero-point vibrational energy corrections. At this level, the mean absolute deviations from the experimental barriers is significantly larger at 7.7 kJ mol-1, the calculated barriers being consistently too high. The effect of quadruple excitations is found to be small. The considerably less expensive B3-LYP/6-311+G(3df,2p)//B3-LYP/6-31G(d) procedure performs quite well, with a mean absolute deviation of about 5.6 kJ mol-1. Solvent effects were estimated using the SCIPCM model. For a dielectric constant of 2 (nonpolar medium), the effect on barrier ranges from −1.1 to +1.1 kJ mol-1, while for a dielectric constant of 40 (polar medium), the effects range from −3.0 to +2.8 kJ mol-1.

Multiphoton upconversion is a process where two or more photons are absorbed simultaneously to excite an electron to an excited state and, subsequently, the relaxation of electron gives rise to the emission of a photon with frequency greater than those of the absorbed photons. Materials possessing such property attracted attention due to applications in biological imaging, photodynamic therapy, three-dimensional optical data storage, frequency-upconverted lasing and optical power limiting. Here we report four-photon upconversion in metal–organic frameworks containing the ligand, trans, trans-9,10-bis(4-pyridylethenyl)anthracene. The ligand has a symmetrical acceptor–π–donor–π–acceptor structure and a singlet biradical electronic ground state, which boosted its multiphoton absorption cross-sections. We demonstrate that the upconversion efficiency can be enhanced by Förster resonance energy transfer within host–guest metal–organic frameworks consisting of encapsulated high quantum yielding guest molecules. Using these strategies, metal–organic framework materials, which can exhibit frequency-upconverted photoluminescence excited by simultaneous multiphoton absorption, can be rationally designed and synthesized.