Publicaciones 2011-2020

@article{RN365,
title = {Polymer-Based Nanocomposites: In Situ Generation and Immobilization of Gold Nanoparticles on Poly(N-Vinyl-2-Pyrrolidone) and Poly(Epsilon-Caprolactone) Thin Films},
author = { M. Mendez-Lopez and C. Saldias and M. Urz\'{u}a and V. Villalobos and M. Schmidt and D. Radic and A. Leiva},
url = {/brokenurl#<Go to ISI>://WOS:000417111000053},
doi = {10.1166/jnn.2017.13868},
issn = {1533-4880},
year = {2017},
date = {2017-01-01},
journal = {Journal of Nanoscience and Nanotechnology},
volume = {17},
number = {12},
pages = {9074-9080},
abstract = {In this work, we report an interesting method for simultaneous obtaining and immobilization of gold nanoparticles onto polymer thin films. Polymer-based nanocomposites were generated by spontaneous adsorption and reduction of Au III ions onto polymeric films surfaces. Poly(N-vinyl-2-pyrrolidone) and poly(epsilon-caprolactone), polymers that have shown their capability to reduce Au III and stabilize the generated gold nanoparticles, were used. The polymer film thickness and hydrophilic or hydrophobic nature of the solid substrate on which the polymers are deposited, directly affect the quantity and characteristics of the gold nanoparticles incorporated in films. Therefore, these parameters can be used to obtain nanocomposites with modulated features. The method presented is a simple route to produce nanocomposites with a high potential for use in diverse technological applications.},
keywords = {chemistry, copolymers, films, gold growth metal nanocomposites, nanoparticles, polymer reducing silver stabilization, step synthesis, thin},
pubstate = {published},
tppubtype = {article}
}

@article{RN362,
title = {Synthesis and Magnetic Properties of Nanostructured Metallic Co, Mn and Ni Oxide Materials Obtained from Solid-State Metal-Macromolecular Complex Precursors},
author = { C. Diaz and M.L. Valenzuela and M.A. Laguna-Bercero and A. Orera and D. Bobadilla and S. Abarca and O. Pena},
url = {/brokenurl#<Go to ISI>://WOS:000402166600064},
doi = {10.1039/c7ra00782e},
issn = {2046-2069},
year = {2017},
date = {2017-01-01},
journal = {Rsc Advances},
volume = {7},
number = {44},
pages = {27729-27736},
abstract = {The simple reaction of chitosan with metallic salts yields (chitosan) (MLn)(x)},
keywords = {chemistry, chitosan, co3o4 crystal-structure, decomposition, gold nanocomposites, nanocrystals, nanoparticles, size, supracrystals},
pubstate = {published},
tppubtype = {article}
}

@article{RN306,
title = {Theoretical Exploration of Seleno and Tellurophenols as Promising Alternatives to Sulfur Ligands for Anchoring to Gold (111) Materials},
author = { S. Miranda-Rojas and R. Salazar-Molina and J. Kastner and R. Arratia-Perez and F. Mendizabal},
url = {/brokenurl#<Go to ISI>://WOS:000369510500023},
doi = {10.1039/c5ra21964g},
issn = {2046-2069},
year = {2016},
date = {2016-01-01},
journal = {Rsc Advances},
volume = {6},
number = {6},
pages = {4458-4468},
abstract = {It is widely known that sulfur ligands, such as alkanethiols or phenothiols and their derivatives, are useful anchor systems for gold materials due to the high affinity of sulfur to gold surfaces. In this study we use DFT calculations and a 42-atom gold cluster model to study the interaction between selenophenol and tellurophenol-derivatives with the Au(111) surface to gain information towards potential new gold-based materials. We modulated the interaction strength by controlling the charge transfer process of a particular interaction by chemically modifying the ligands. To obtain a complete analysis, we studied the ligands in their protonated, anionic and radical states aiming to cover the three possibilities in which these may interact with the gold cluster. In order to get a deeper insight into the nature of the interaction we used several analysis techniques such as energy decomposition analysis (EDA), non-covalent interactions (NCI) and natural population analysis (NPA). Our results reveal that tellurium in the anionic state provides complexes of better thermodynamic stability by similar to 12.0 kcal mol, when compared with the strongest sulfur-gold complex, also in the anionic state. Furthermore, this indicates that the anionic ligand is probably the dominant state for both selenium and tellurium as observed previously for sulfur. The extent to which the interaction strength could be controlled directly depends on the state of the anchor atom. In our case the anionic state is the most suitable for tuning the interaction. Finally, our main findings suggest that exchanging sulfur with selenium or tellurium involves an important increase of the interaction strength, thus, making these selenophenol and tellurophenol derivatives attractive for the development of new functional materials.},
keywords = {basis-sets, chain-length, charge-transfer, chemistry, complexes, interface, monolayers, nanoparticles, pseudopotentials, self-assembled tellurium titanium},
pubstate = {published},
tppubtype = {article}
}

@article{RN320,
title = {A Computational Study of Structure and Reactivity of N-Substitued-4-Piperidones Curcumin Analogues and Their Radical Anions},
author = { M. Martinez-Cifuentes and B. Weiss-Lopez and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000392140100052},
doi = {10.3390/molecules21121658},
issn = {1420-3049},
year = {2016},
date = {2016-01-01},
journal = {Molecules},
volume = {21},
number = {12},
abstract = {In this work, a computational study of a series of N-substitued-4-piperidones curcumin analogues is presented. The molecular structure of the neutral molecules and their radical anions, as well as their reactivity, are investigated. N-substituents include methyl and benzyl groups, while substituents on the aromatic rings cover electron-donor and electron-acceptor groups. Substitutions at the nitrogen atom do not significantly affect the geometry and frontier molecular orbitals (FMO) energies of these molecules. On the other hand, substituents on the aromatic rings modify the distribution of FMO. In addition, they influence the capability of these molecules to attach an additional electron, which was studied through adiabatic (AEA) and vertical electron affinities (VEA), as well as vertical detachment energy (VDE). To study electrophilic properties of these structures, local reactivity indices, such as Fukui (f(+)) and Parr (P+) functions, were calculated, and show the influence of the aromatic rings substituents on the reactivity of alpha,beta-unsaturated ketones towards nucleophilic attack. This study has potential implications for the design of curcumin analogues based on a 4-piperidone core with desired reactivity.},
keywords = {anion, anticancer, chemistry, computational curcumin, derivatives, in-vitro, indices, radical reactivity stability, targets},
pubstate = {published},
tppubtype = {article}
}

@article{RN253,
title = {Theoretical Study on Interactions of Fluorinated Organomercurials with Arene and Gold Fragments},
author = { F. Mendizabal and S. Miranda-Rojas and L. Barrientos-Poblete},
url = {/brokenurl#<Go to ISI>://WOS:000362291300083},
doi = {10.1039/c5cp04503g},
issn = {1463-9076},
year = {2015},
date = {2015-01-01},
journal = {Physical Chemistry Chemical Physics},
volume = {17},
number = {39},
pages = {26417-26428},
abstract = {The electronic structure and spectroscopic properties of [Hg(C6F5)(2)](2)-(L); [Hg-3(o-C6F4)(3)](2)center dotL (L = naphthalene, biphenyl, fluorene) and [Hg-3(o-C6F4)(3)]Au-3(mu-C(OEt)=NC6H4CH3)(3)(n) (n = 1, 2) adducts were studied at the HF, MP2, SCS-MP2, DFT and DFT-D3 levels. The intermolecular interactions among the fragments were analyzed using the levels of calculations proposed. The energy decomposition analysis at the TPSS-D3 level was used to define the dominant components of the interaction. The van der Waals interactions between mercury and arene (Hg-arene) were found to be the main short-range stability contribution in the [Hg(C6F5)(2)](2)-L and [Hg-3(o-C6F4)(3)](2)center dotL complexes. At the MP2, SCS-MP2 and DFT-D3 levels, equilibrium Hg-C distances are between 360 and 310 pm. The pair-wise energies were found to be between 18.0 and 6.0 kJ mol(-1). In the [Hg-3(o-C6F4)(3)]Au-3(mu-C(OEt)=NC6H4CH3)(3)(n) (n = 1, 2) complexes the metallophilic intermolecular interaction is Hg-Au. Pair-wise energies of 85.7, 39.4, 78.1 and 57.9 kJ mol(-1) were found at the MP2, SCS-MP2, TPSS-D3 and PBE-D3 levels using the [Hg3(o-C6F4) 3] Au-3(mu-C(OEt)=NC6H4CH3)(3) model. The same trend is maintained for the [Hg-3(o-C6F4)(3)]Au-3(mu-C(OEt)=NC6H4CH3)(3)(2) model: 73.4, 29.3, 70.6 and 61.3 kJ mol(-1) by MP2, SCS-MP2, TPSS-D3 and PBE-D3, respectively. The absorption spectra of these complexes were calculated using the single excitation time-dependent method at the TPSS-D3 level to validate the models against the experimental data.},
keywords = {attraction, au-i, chemistry, closed-shell complexation, coordination, energies, hg-ii, mercury},
pubstate = {published},
tppubtype = {article}
}

@article{toro2014urban,
title = {Urban Atmospheric Ammonia in Santiago City, Chile},
author = { R. Toro and M. Canales and R. Flocchini and R.G.E. Morales and M.A. Leiva},
url = {/brokenurl#<Go to ISI>://WOS:000331789600004},
doi = {10.4209/aaqr.2012.07.0189},
issn = {1680-8584},
year = {2014},
date = {2014-01-01},
journal = {Aerosol and Air Quality Research},
volume = {14},
number = {1},
pages = {33-44},
abstract = {To improve the current understanding of the ammonia distribution in the major urban area of Chile, measurements of atmospheric NH3 were collected in Santiago during three sampling periods (25 April to 27 May, 11 to 26 June and 27 June to 31 July 2008). Additionally, air quality and meteorological data as well as NH4+, NO3-},
keywords = {air ammonia ammonia, chemistry, chile, emissions, environmental chemistry, gaseous new-york, nh3, nitrogen, particulate passive pm2.5, quality, samplers, santiago, secondary sulfate, uncertainty},
pubstate = {published},
tppubtype = {article}
}

@article{RN215,
title = {Intramolecular Hydrogen Bond in Biologically Active O-Carbonyl Hydroquinones},
author = { M. Martinez-Cifuentes and B. Weiss-Lopez and L.S. Santos and R. Araya-Maturana},
url = {/brokenurl#<Go to ISI>://WOS:000340036200041},
doi = {10.3390/molecules19079354},
issn = {1420-3049},
year = {2014},
date = {2014-01-01},
journal = {Molecules},
volume = {19},
number = {7},
pages = {9354-9368},
abstract = {Intramolecular hydrogen bonds (IHBs) play a central role in the molecular structure, chemical reactivity and interactions of biologically active molecules. Here, we study the IHBs of seven related o-carbonyl hydroquinones and one structurally-related aromatic lactone, some of which have shown anticancer and antioxidant activity. Experimental NMR data were correlated with theoretical calculations at the DFT and ab initio levels. Natural bond orbital (NBO) and molecular electrostatic potential (MEP) calculations were used to study the electronic characteristics of these IHB. As expected, our results show that NBO calculations are better than MEP to describe the strength of the IHBs. NBO energies (Delta E-ij((2))) show that the main contributions to energy stabilization correspond to LP ->sigma* interactions for IHBs, (O1O2)-O-center dot center dot center dot-H-2 and the delocalization LP ->pi* for O-2-C-2 = C-alpha(beta). For the (O1O2)-O-center dot center dot center dot-H-2 interaction, the values of Delta E-ij((2)) can be attributed to the difference in the overlap ability between orbitals i and j (F-ij), instead of the energy difference between them. The large energy for the LP O-2 ->pi* C-2 = C-alpha(beta) interaction in the compounds 9-Hydroxy-5-oxo-4,8, 8-trimethyl-1, 9(8H)-anthracenecarbolactone (VIII) and 9,10-dihydroxy-4,4-dimethylanthracen-1(4H)-one (VII) (55.49 and 60.70 kcal/mol, respectively) when compared with the remaining molecules (all less than 50 kcal/mol), suggests that the IHBs in VIII and VII are strongly resonance assisted.},
keywords = {ab-initio, bond bond, chemistry, derivatives, dft, diels-alder electrostatic hydrogen hydroquinone, inhibitors, molecular molecules, natural orbital, potential, quinones, radicals reaction, resonance, respiration, tumor-cell},
pubstate = {published},
tppubtype = {article}
}

@article{RN82,
title = {Theoretical Study on Electronic Spectra and Interaction in [Au-3]-L-[Au-3] (L = C6f6,Ag+) Complexes},
author = { F. Mendizabal and R. Salazar},
url = {/brokenurl#<Go to ISI>://WOS:000318274700006},
doi = {10.1007/s00894-012-1570-5},
issn = {1610-2940},
year = {2013},
date = {2013-01-01},
journal = {Journal of Molecular Modeling},
volume = {19},
number = {5},
pages = {1973-1979},
abstract = {The electronic structure and spectroscopic properties of [Au-3(mu-C(OEt) = NC6H4CH3)(3)](n)-(C6F6)(m) and [Au-3(mu-C-2,N-3-bzim)(3)](n)-(Ag+)(m) were studied at the B3LYP, PBE and TPSS levels. The interaction between the [Au-3] cluster and L (C6F6, Ag+) was analyzed. Grimme's dispersion correction is used for those functionals. Weak pi-interactions (Au-C6F6) were found to be the main contribution short-range stability in the models; while in the models with Ag+, an ionic interaction is obtained. The absorption spectra of these models at the PBE level agree with the experimental spectra.},
keywords = {approximation, attraction, chemistry, dimers electronic energies, interaction, mercury, photophysics, secondary spectra},
pubstate = {published},
tppubtype = {article}
}

@article{RN160,
title = {Ozone Distribution in the Lower Troposphere over Complex Terrain in Central Chile},
author = { R.J. Seguel and C. Mancilla and R. Rondanelli and M.A. Leiva and R.G.E. Morales},
url = {/brokenurl#<Go to ISI>://WOS:000319618300021},
doi = {10.1002/jgrd.50293},
issn = {2169-897x},
year = {2013},
date = {2013-01-01},
journal = {Journal of Geophysical Research-Atmospheres},
volume = {118},
number = {7},
pages = {2966-2980},
abstract = {Observations were performed in 12 communities of Central Chile in order to determine the horizontal gradients of ozone in the Santiago Basin and surrounding valleys. Higher ozone mixing ratios were found northeast of the Santiago Basin and included east of the Aconcagua Valley (similar to 70km from Santiago) suggesting that photochemical pollution produced in Santiago is capable of passing through the Chacabuco mountain chain (similar to 1.3km) and have impact downwind from the regions with the largest NOx and VOC emissions. To complement existing surface observations, ozonesonde and tethersonde campaigns were performed in the Santiago Basin and the Aconcagua Valley. The results suggest ozone can accumulate in layers aloft (e.g., >102ppb at 2km) similarly to layers observed in complex topography coastal regions like Southern California. Layers of significant ozone concentrations having a near surface origin were observed above the mixed layer and below the subsidence inversion base. We propose that the ozone in this residual layer can be transported large distances (at least to 70km) to further penetrate into the local environment under conditions of a well-mixed boundary layer.},
keywords = {boundary-layer, california, chemistry, chile, environmental chemistry, evolution, hydrocarbons, layer, metropolitan-area, model organic-compounds, ozone, ozonesondes, photochemical planetary residual santiago, smog, volatile},
pubstate = {published},
tppubtype = {article}
}

@article{RN29d,
title = {Influence of Tio2 on Prebiotic Thermal Synthesis of the Gly-Gln Polymer},
author = { P. Leyton and R. Saladino and C. Crestini and M. Campos-Vallette and C. Paipa and A. Berrios and S. Fuentes and R.A. Zarate},
url = {/brokenurl#<Go to ISI>://WOS:000304150300004},
doi = {10.1007/s00726-011-0939-6},
issn = {0939-4451},
year = {2012},
date = {2012-01-01},
journal = {Amino Acids},
volume = {42},
number = {6},
pages = {2079-2088},
abstract = {The role of the titanium dioxide (rutile and anatase) with and without room light on the thermal synthesis of the glycine--glutamine (Gly-Gln) polymer is described. The efficiency in percentage of polymerization with room light was increased in 6% in the presence of rutile and in 23% in the presence of anatase. The thermal synthesis in the molten state was carried out in the absence and presence of both oxides. In all cases, the vibrational spectra showed characteristic group frequencies corresponding to a polypeptide structure. No spectral differences were observed by room light effect on the polymer on rutile. However, the polymer obtained in the presence of anatase and room light shows spectral changes associated with the formation of shorter new abundant and conformationally different species compared with the original polymer. The SEM-EDX characterization of the solid phase involved in the thermal synthesis showed that the morphology of the polypeptide is different in the presence of rutile compared to anatase. The SDS-PAGE and GPC results suggest that smaller chains are formed in the presence of both oxides and the distribution of the size and weight of each polymer molecule is completely different when the condensation is performed in the presence of anatase or rutile. Nuclear magnetic resonance analyses confirmed the incorporation of both Gly and Gln residues in the polymers, with a prevalence of Gly. Both possible sequences -GlyGln- and -GlnGly- were also detected.},
keywords = {amino-acids, chemistry, condensation conditions, crystalline diketopiperazine, dioxide, dynamics, earth formation ft-ir glutamic glycine, peptide prebiotic primitive reaction, self-disproportionation, spectra, spectroscopy, synthesis, thermal titanium vibrational},
pubstate = {published},
tppubtype = {article}
}

@article{mendizabal2011theoretical,
title = {Theoretical Study of the Protonation of [Pt-3(Mu-L)(3)(L ')(3)] (L = Co, So2, Cnh; L ' = Ph3, Cnh)},
author = { F. Mendizabal and D. Donoso and D. Burgos},
url = {/brokenurl#<Go to ISI>://WOS:000295831700035},
doi = {10.1016/j.cplett.2011.08.068},
issn = {0009-2614},
year = {2011},
date = {2011-01-01},
journal = {Chemical Physics Letters},
volume = {514},
number = {4-6},
pages = {374-378},
publisher = {2011 Elsevier B. V.},
abstract = {Ab initio calculations suggest that a series of clusters of the [Pt-3(mu-L)(3)(L')(3)(mu(3)-H](+) type (L = CO, SO2, CNH; L' = PH3, CNH) are stable. We have studied these clusters at the HF, MP2, B3LYP, PBE and TPSS theory levels. The magnitude of the interaction energies and distances indicates a substantial covalent character of the Pt-3-H bond, confirmed by orbital diagrams. In addition, the Fukui index of electrophilic attack and electrophilicity index on the unprotonated clusters were used to explore possible sites where chemical reactivity may play a role.},
keywords = {approximation, chemistry, cluster complexes, electrophilicity hydride, index, molecules, systems, units},
pubstate = {published},
tppubtype = {article}
}

@article{RN6c,
title = {Basicity of Bisperhalophenyl Aurates toward Closed-Shell Metal Ions: Metallophilicity and Additional Interactions},
author = { J.M. Lopez-De-Luzuriaga and M. Monge and M.E. Olmos and M. Rodriguez-Castillo and A. Laguna and F. Mendizabal},
url = {/brokenurl#<Go to ISI>://WOS:000290572300031},
doi = {10.1007/s00214-011-0902-3},
issn = {1432-881x},
year = {2011},
date = {2011-01-01},
journal = {Theoretical Chemistry Accounts},
volume = {129},
number = {3-5},
pages = {593-602},
abstract = {The interaction of bisperhalophenyl aurates [AuR2](-) (R = C6F5, C6F3Cl2, and C6Cl5) with the closed-shell Ag+, Cu+, and Tl+ ions has been studied theoretically and compared with the experimentally known X-ray diffraction crystal structures. Initially, the aurates have been fully optimized at MP2 level of theory in a D (2h) symmetry. The analysis of the basicity of the three aurates [AuR2](-) (R = C6F5, C6F3Cl2 and C6Cl5) against Ag+ ions in a C (2v) symmetry has been calculated in point-by-point bsse-corrected interaction energy analysis at HF and MP2 levels of theory. Taking into account the experimental observation of additional interactions between the heterometals and C (ipso) atoms at the perhalophenyl rings or halogen atoms at the ortho position of the perhalophenyl rings, dinuclear models of the type [AuR2](-)center dot center dot center dot Ag+ (R = C6Cl5, and C6F5); [AuR2](-)center dot center dot center dot Cu+ (R = C6F5, and C6Cl5) and [AuR2](-)center dot center dot center dot Tl+ (R = C6F5, and C6Cl5) with a C (2v) , C (2) , and C (s) symmetries have been optimized at DFT-B3LYP level. The interaction energies have been computed through bsse-corrected single point HF and MP2 calculations. The energy stabilization provided and the heterometal preference have been analyzed and compared with the experimental results.},
keywords = {au, chemistry, complexes copper, gold, interactions, metal-metal silver, thallium, theoretical},
pubstate = {published},
tppubtype = {article}
}