Doing ab initio molecular dynamics simulations, we demonstrate a possibility of hydrogenation of carbon monoxide producing methanol step by step. At first, the hydrogen atom reacts with the carbon monoxide molecule at the excited state forming the formyl radical. Formaldehyde was formed after adding one more hydrogen atom to the system. Finally, absorption of two hydrogen atoms to formaldehyde produces methanol molecule. This study is performed by using the all-electron mixed basis approach based on the time dependent density functional theory within the adiabatic local density approximation for an electronic ground-state configuration and the one-shot GW approximation for an electronic excited state configuration.

The microstructures of the Ti–V alloy are studied by purely first-principles calculations without relying on any empirical or experimental parameter. The special quasirandom structure model is employed to treat the all-proportional solid solution $$\beta$$ β phase, while the first-principles phase field method or its variant is employed to treat the coexistence phases. The linearity of the calculated local free energy against the integer Ti$$_n$$ n V$$_m$$ m composition in the cluster expansion method manifests a clear evidence of the solid solution behavior. From a detailed energy comparison, our results are consistent with the experimental fact that the Ti–V alloy is an all-proportional solid solution of the $$\beta$$ β phase at high temperatures and exhibits an $$\alpha +\beta$$ α + β coexistence at low temperatures. Moreover, it is found that mosaic-type microstructures may appear as a metastable phase, as observed by many experiments. The first-principles criterion for the all-proportional solid solution behavior presented in this paper is very general and can be applied to any other binary or multi-component alloys.

is an α + β titanium alloy, in which the alloying components strongly affect the mechanical properties. In this report, element partitioning effects in Ti64 are investigated by using the first-principles phase field (FPPF) method, which has recently been proposed by our group. In the FPPF method, the local free energy is calculated using cluster expansion method in combination with density functional theory and the temperature effect is incorporated using potential renormalization theory. We have succeeded in identifying enrichment of Al (V) in the α (β) phase, i.e., the clear evidence for the element partitioning effects of Al and V, without using any thermodynamical parameter. The transformation of the β phase and the α phase in microstructure is investigated by varying the V and Al concentration by a small amount. Our results are in excellent agreement with the recent experimental results, showing the validity of the FPPF method for ternary alloys.

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