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The resultant energy of solvent H–O bond exothermic elongation by O:⇔:O repulsion, featured at <3100 cm −1 , and the solute H–O bond endothermic contraction by bond-order-deficiency, at 3610 cm −1 , heats up the (Li, Na, K)OH solutions. The solution temperature increases linearly with the number fraction of the ordinary O:H–O bonds transiting into their hydration states. The elongated H–O bond emits >150% the O:H cohesive energy of 0.095 eV that caps the energy dissipating by molecular motion, thermal fluctuation, diffusion, and even evaporation. Therefore, the intramolecular H–O bond relaxation dictates the OH − solvation bonding thermodynamics and the performance of basic solutions. [ABSTRACT FROM AUTHOR]

Abstract: The 2p3/2 core-level binding energy (BE) shifts of Fe surface and Fe nanoparticles have been analyzed by considering the bond order-length-strength (BOLS) correlation mechanism in decomposition of the X-ray photoelectron spectrum (XPS). It turns out that the Fe 2p3/2 BE shifts positively by 2.17eV from the atomic value of 704.52eV to the bulk value of 706.69eV and that a further 0.32 and 0.16eV positive shift occurs, respectively, to the top and the second atomic layers. Consistency between BOLS predictions and the measured size dependence of BE shift clarifies the dominance of the broken-bond-induced local strain and quantum trapping in perturbing the Hamiltonian and hence the positive shift of the 2p3/2 BE of Fe surface and Fe nanostructures. [Copyright &y& Elsevier]

We show the reconciliation of the strain ( ε )-, pressure ( P )-, and layer-number ( N )-dependence of the phonon frequency and photon energy shifts for MX 2 in terms of stimulated bond relaxation, with quantification of the coefficients of bond length and energy relaxation, the bond nature index, force constant, and cohesive energy density. We found that (i) atomic under-coordination shortens and stiffens the M–X bond, which widens the bandgap; (ii) the directional strain governs phonon-frequency splitting and narrowing; and (iii) homogenous mechanical compression induces the opposite effect of stretching. [ABSTRACT FROM AUTHOR]

We examined the combined effect of atomic under- and hetero-coordination on the bond relaxation and electronic binding energy of Sc, Zr, and ScZr alloying using a combination of the bond-order–length–strength (BOLS) correlation and density functional theory (DFT) calculations. Observations strongly emphasize the relevance of core-level shifts as reliable X-ray photoelectron spectroscopy experimental descriptors of core–shell catalysis reactivity, along with under-coordinated atoms in bimetallic transition metal systems. The BOLS–DFT method provides enhanced catalysis reactivity and detects surface and alloy configurations, opening up the possibility to investigate more complex systems with irregularly under- and hetero-coordinated atoms. [ABSTRACT FROM AUTHOR]

A combination of the photoelectron spectrometrics and density functional theory calculations has confirmed bond-order-length-strength (BOLS) predictions on the atomic undercoordination induced local bond contraction, charge densification and bond energy entrapment of lithium (Li) atomic clusters and layer-resolved Li(1 1 0) skins. Analysis also derives the energy level of an isolated Li atom and its shift upon bulk and skin formation, which is beyond the scope of currently available approaches. [ABSTRACT FROM AUTHOR]

Highlights: [•] Bond order (z), length (d), and strength (E) determine the Raman shift, Δω. [•] Heating (T) and bond order (z) variation vary the d, E, and Δω. [•] Raman shift of nanocrystals results from the bond relaxation in the skin region. [•] Δω(T) results in the atomic cohesive energy and Debye temperature. [•] Δω(z) leads to the bond nature index and the reference ω from which the Δω proceeds. [Copyright &y& Elsevier]

Abstract: We have investigated the joint effect of size- and composition-induced band-gap change of semiconductive nanocompounds from the recently developed bond-order-length-strength (BOLS) correlation mechanism using the approach of local bond average (LBA). An analytical solution has been developed to connect the band-gap energy with the bonding identities of the nanocompounds. Agreement between the model predictions with the available experimental measurements of band-gap change of II–VI semiconductor nanocompounds showed that both the particle size and the composition with alloying effect can be used as factors tuning the band-gap energy, suggesting an effective way to realize the desirable properties of semiconductive nanocompounds. [Copyright &y& Elsevier]