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Recently, P. V. Nhat et al., have discussed and commented on our article (DOI: 10.1039/D0CP04018E) for the case of the most stable structure of Ag15. They have found a new most stable structure (labeled as 15-1) in comparison to the putative global minimum reported by us, which is a four layered 1-4-6-4 stacking structure with a C2v point group (15-2). In this reply, we have performed a larger structure search which allowed us to confirm the results of Nhat et al. The results show the existence of multiple isoenergetic isomers with similar structure motifs for the Ag15 system, increasing the problem complexity to locate the global minimum. The results in regard to the structure and electronic properties of the new lowest energy structure are discussed.

In the present work, the lowest energy structures and electronic properties of Agn clusters up to n = 16 are investigated using a successive growth algorithm coupled with density functional theory calculations (DFT). In the literature, a number of putative global minimum structures for silver clusters have been reported by using different approaches, but a comparative study for n = 15-16 has not been undertaken so far. Here, we perform a comparative study using the PW91/cc-pVDZ-PP level to more precisely determine the optimal configuration. For Ag15, the most stable configuration is a four layered 1-4-6-4 stacking structure with C2v symmetry. For Ag16 a new most stable form is found with a 1-4-2-5-1-3 stacking structure in the singlet state, slightly more stable than the putative global minimum reported. By means of the electrostatic potential, the new putative global minimum has been found to be more reactive, and the active sites of the clusters were identified and confirmed with the interaction energy. The electronic and vibrational properties are found to be in good agreement with the available experimental data. Theoretical data on the infrared spectra of the clusters is also provided.

Gold clusters are useful templates for nanosized species retaining a distinctive size-dependent behavior. Usually, a ligand-protected shell passivates such clusters, where their properties can be p...

Different theoretical methodologies were applied to a series of substituted benzenes C6X6 (with X = H, F, Cl, Br and I) to pursue the property of aromaticity. HOMA (as structural criterion), NICS (FIPC-NICS, isotropic and ZZ employed as magnetic criteria) as well as the indexes ASE, MCI, PDI and FLU, interestingly provided controversial data respect to the magnetically induced current density plots and chemical intuition, which is extensively discussed in the herein work. Furthermore, EDA-NOCV was used to complement the rational explanation of the observed results.

In this letter, we discussed the plausible formation of [Au11Re] as a superatom with an electronic structure accounted by the 1S21P61D10 shell order, denoting similar stability to [W@Au12]. The possible hollow or endohedral structures show a variable HOMO-LUMO gap according to the given structure (from 0.33 to 1.30 eV, at the PBE/ZORA level). Our results show that the energy minimum is an endohedral arrangement, where Re is encapsulated in a D3h-Au11 cage, retaining a higher gold-dopant stoichiometric ratio. This approach is useful for further rationalization and design of novel superatoms expanding the libraries of endohedral clusters.

The use of a new copper(I) coordination polymer (CP) as additive in transparent composite films of 190 nm of thickness for ultraviolet (UV) shielding is presented. The luminescent 1-D Cu(I) CP was easily synthesized through a self-assembly process between Cu(I) iodide and 2,6-bis(1H-benzotriazol-1-ylmethyl)pyridine (L). The CP, [Cu2(μ − I)2(μ − L)2]n, was structurally characterized by infrared, UV–visible diffuse reflectance and photoluminescence spectroscopy, elemental and thermogravimetric analyses, single-crystal and powder X-ray diffraction, and relativistic density functional theory calculations. The CP was dispersed and immobilized into a polymeric matrix in the presence of Sudan I, yielding a composite material that exhibits a reduction of 49% of the UV transmittance at 350 nm. Thus, the use of a new Cu(I) CP in polymeric composite films appears as a novel approach toward ultrathin and transparent UV shielding films, which have potential applications as protection layers of paints and coatings that tend to degrade when exposed to UV radiation.

In this article, we employed density functional theory calculation methods to determine the relationship between the chemical hardness (η), intermolecular chemical hardness (η DA), and nucleophilicity (N) chemical reactivity descriptors, as well as the energy of the occupied frontier orbitals (E a1g), and the electrocatalytic activity of different metallophthalocyanines [MPc’s with M=Cr(II), Mn(II), Fe(II), Co(I), Ni(II), and Cu(II)] for the oxygen reduction reaction. Our results suggest that η DA, N, and E a1g are appropriate parameters to estimate the electrocatalytic activity. On the other hand, the type of the metallic center determines the strength of the oxygen-binding energy, where a strong electronic interaction promotes the efficient electro-reduction of the dioxygen molecule, which is observed experimentally as a high catalytic activity.

Gold–graphene interaction at the interface is evaluated through different polyaromatic hydrocarbons (PAH), accounted by C6H6, C24H12, C54H16, and C96H18, focusing into different energetic terms related to the overall interaction. Our results characterize the neutral gold–PAH interaction nature with 45% of dispersion character, 35% of electrostatic, and 20% of covalent character, suggesting that moderate van der Waals character is mostly involved in the interaction, which increases according to the size of the respective PAH. The resulting surface charge distribution in the graphene model is a relevant parameter to take into account, since the ability of the surface charge to be reorganized over the polycyclic structure in both contact and surrounding regions is important in order to evaluate interactions and different interacting conformations. Our results suggest that for a Au12 contact surface of radius 4.13 A, the covalent, electrostatic and dispersion character of the interaction are effectively accou...

In this article, we simulated the collisions of an OH• projectile impacting on a methanol cluster formed by ten units of methanol to mimic an ice mantle (CH3OH)10. The chemical processes occurring after the impact were studied through Born-Oppenheimer (ab-initio) molecular dynamics. We focus on collisions with initial kinetic impact energy of 10–22 eV, where the richest chemistry happens. We report the formation mechanisms of stable complex organic molecules (COMs) such as methoxymethanol CH3OCH2OH, formic acid HCOOH, formyl radical HCO, formaldehyde H2CO and its elusive HCOH isomer. We show that CH2(OH)2, •CH2OH or +CH2OH are key intermediates to generate H2CO and other COMs. We compare the outcomes using OH• with those using OH− projectiles. These processes are likely relevant to the production of COMs in astrophysical environments. We discuss its formation mechanism and the astrophysical implications of these chemical pathways in star-forming regions.

Here we discussed the plausible formation of the Cu10Ru cluster as a superatomic specie accounted for its 1S21P61D10 shell order. By stochastic structure search on Cu10Ru clusters, we found six low-lying cluster isomers with ΔE values from 0.0 to 4.7 kcal∙mol above the ground state denoting an endohedral motif with the Ru dopant inside the Cu10 cage. By using molecular dynamics simulations we found a clear trend of encapsulation of the Ru atom at low temperatures. These results are useful for further rationalization and design of novel spherical superatoms expanding the libraries of stable endohedral clusters.