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Tuning of micro‐ and macro‐structures of hard carbon is important for expanding its properties. However, achieving controlled and integrated modulation of the micro‐ and macro‐structures of such materials remains a challenge. An intermolecular hydrogen bond‐driven interfacial cooperative‐assembly and then polymerization strategy is reported herein: micelles‐glucose molecules are used for the synthesis of wrinkled hard carbon spheres with precisely tunable crystallinity. As intermolecular hydrogen is positioned bonds to achieve an anchoring effect, which facilitates immobilization of glucose molecules at the molecular level during the assembly and subsequent dehydration‐aromatization. In virtue of controlling the micelle concentration, the density of intermolecular hydrogen bonding interactions is precisely regulated. As a result, the yielded hard carbon spheres exhibited excellent sodium‐ion storage performance because of their high crystallinity and exposed surfaces. By establishing a simple micelle–based interfacial reaction strategy, the study leverages optimized intermolecular hydrogen bond anchoring effects to tailor the properties of materials at a molecular level. [ABSTRACT FROM AUTHOR]

The molecular structure of the tripodal carbamoylmethylphosphine oxide compound diethyl {[(5-[2-(diethoxyphosphoryl)acetamido]-3-{2-[2-(diethoxyphosphoryl)acetamido]ethyl}pentyl)carbamoyl]methyl}phosphonate, C25H52N3O12P3, features six intramolecular hydrogen-bonding interactions. The phosphonate groups have key bond lengths ranging from 1.4696 (12) to 1.4729 (12) Å (P=O), 1.5681 (11) to 1.5811 (12) Å (P—O) and 1.7881 (16) to 1.7936 (16) Å (P—C). Each amide group adopts a nearly perfect trans geometry, and the geometry around each phophorus atom resembles a slightly distorted tetrahedron.

The molecular structure of the tripodal carbamoylmethylphosphine oxide compound diethyl {[(5-[2-(diethoxyphosphoryl)acetamido]-3-{2-[2-(diethoxyphosphoryl)acetamido]ethyl}pentyl)carbamoyl]methyl}phosphonate, C25H52N3O12P3, features six intramolecular hydrogen-bonding interactions. The phosphonate groups have key bond lengths ranging from 1.4696 (12) to 1.4729 (12) Å (P=O), 1.5681 (11) to 1.5811 (12) Å (P—O) and 1.7881 (16) to 1.7936 (16) Å (P—C). Each amide group adopts a nearly perfect trans geometry, and the geometry around each phophorus atom resembles a slightly distorted tetrahedron. [ABSTRACT FROM AUTHOR]

In the present research, thermal investigation of amorphous solid dispersions (ASDs) was performed in order to compare their relaxation transitions. Two different active pharmaceutical ingredients (APIs), namely naproxen (NAP) and spironolactone (SPIR), were used as model drugs and combined with polyvinylpyrrolidone vinyl acetate (PVPVA64) copolymer to form stable ASDs. The reason for the API selection was their different interacting potentials based on the presence (in the case of NAP) and the lack of H-bond donor group (in the case of SPIR). Determination of both Tg and sub-Tg transitions suggested that ASDs containing NAP and PVPVA64 are 'interacting' systems with respect to the H-bonding. Besides, temperature-dependent Raman spectroscopic experiments confirmed that the naphthalene ring of the NAP has a significant role in the sub-Tg relaxations. In contrast, SPIR-PVPVA64 systems proved to be 'non-interacting' ASDs according to the MDSC, TSDC, and Raman measurements. This study highlights that the combination of the results of different thermoanalytical investigations with spectroscopic methods helps to understand the molecular background of the relaxations in ASDs and thus contributes to the conscious design of stable amorphous pharmaceuticals in the early stage of development. [ABSTRACT FROM AUTHOR]

A theoretical investigation of the microsolvation effect on proton exchange (PE) between carbonic acid and methylamine (CA-MTA) has been explored by quantum dynamics simulations. The structural, energy, and dynamic properties of the CA-MTA complex with and without an explicit water molecule are elucidated at the molecular level. The reactions from this study have been clarified into different types: single-step PE (SSPE) and stepwise PE (SWPE). Without the water molecule, the SSPE mechanism is hardly found but observable with a low probability of 0.2. In particular, the water molecule interacting through intermolecular hydrogen-bonded network between CA and MTA in CA-MTA-Win could affect PE by showing both SSPE and SWPE mechanisms. In addition, the existing water molecule plays the significant role in shortening intermolecular hydrogen bonding interactions within the complex resulting in increasing the probability of PE up to 0.92 especially in CA-MTA-Wout. Hence, one water molecule could be used to provide reliable results to represent the significant activity that occurs for the proton exchangeability of the CA and MTA complex.

• The H 2 →N 3 process of 2,4-bImP in AcOH solvent is an intermolecular process. • Its intramolecular proton transfer process promotes second-step H 2 →N 3 process. • Explicit solvent induces fluorescence enhancement and wavelength blue shift. • Explicit solvent molecules have great influence on the ICT process of 2,4-bImP. The excited-state proton transfer process induces unique photophysical properties in organic molecules, which have been extensively applied in new optoelectronics, fluorescent dyes, photocatalysis, and other fields. Experimentally, a new organic molecule (2,4-bis(4,5-diphenyl-1H-imidazol-2-yl)phenol (2,4-bImP)) first synthesized with photochromic behavior triggered by the excited-state intramolecular proton transfer process. However, the specific theoretical details of the excited-state transfer process of this molecule were not provided. In this work, we utilized density functional theory and time-dependent density functional theory to investigate the influence of explicit solvent molecules on the excited-state double proton transfer process of this molecule. The results show that the formation of intermolecular hydrogen bonds between 2,4-bImP and two explicit solvent molecules can effectively reduce the energy barrier for excited-state double proton transfer. One molecule directly participates in the proton transfer process by establishing an intermolecular hydrogen bond bridge with the 2,4-bImP molecule, while the other molecule indirectly reduces the proton transfer energy barrier by weakening the electronegativity of the donor O atom of intramolecular hydrogen bond. This work allows us to realize the important role that explicit solvent molecules play in the proton transfer and photophysical properties of fluorescent molecules, and provides new insights and ideas for the development and design of novel fluorescent molecules. [ABSTRACT FROM AUTHOR]

• Densities and excess volumes for propylene glycol methyl ether + 1,2-propylenediamine. • Viscosities and viscosity deviation for propylene glycol methyl ether + 1,2-propylenediamine. • Form of HBs as OH···NH 2 in propylene glycol methyl ether + 1,2-propylenediamine. In this work, the systematic measurements of physicochemical properties, viz., density (ρ) and viscosity (η) values of propylene glycol methyl ether (PGME) + 1,2-propylenediamine (1,2-PDA) binary system, including pure substances, over the entire mole fraction range at the temperatures of T/K = (298.15 to 318.15) under atmospheric pressure of P = 100.5 kPa. The fundamental data were used to calculate several excess properties, including excess molar volume (V m E), viscosity deviation (Δ η), and excess activation Gibbs free energy (Δ G ∗ E). Meanwhile, the work further investigated the values of thermal expansion coefficient (α p), partial molar volume ( V ¯ ) and apparent molar volume (V φ), thereby offering a comprehensive understanding on non-ideal behavior of the binary system. Furthermore, the variations in ρ values with various molar ratios and temperatures were evaluated through Jouyban-Acree model and nonlinear least squares method. Simultaneously, Grunberg-Nissan model, Eyring-Margules model, Heric model, and McAllister model, were used to fit the dependence of η values on the molar ratio. Arrhenius equation was employed to fit the temperature dependency of η values. In addition, Redlich-Kister (R-K) equation was utilized to fit the V m E , Δ η , and Δ G ∗ E values of binary system. Based on spectral analyses of Raman, ultra-violet (UV), and 1H Nuclear Magnetic Resonance (NMR) and density functional theory (DFT) calculation, the intermolecular hydrogen bond (IHB) of PGME with 1,2-PDA was discussed in depth. [ABSTRACT FROM AUTHOR]