About
The IQTCUB is integrated by more than 60 researchers, experts in several fields of the Theoretical and Computational Chemistry
- About IQTC
  The Institute of Theoretical and Computational Chemistry of the Universitat de Barcelona (IQTCUB) is integrated by more than 60 researchers, experts in several fields of the Theoretical and Computational Chemistry. The research activity carried out at the IQTCUB covers methods and computational tools development, application of several techniques of electronic structures and simulation to problems in materials science, the study of reactivity and reaction dynamics in chemical reactions as well as of biological systems and soft-matter. The main goal is to generate synergies between researchers encouraging the interdisciplinary activities that allow to tackle new challenges. Another important goal is to share expertise in handling the computational resources, which are the main tools in this type of research. See the IQTCUB director’s welcome. For a more detailed information see the 2017 IQTCUB Scientific Activity Report and the XRQTC disseminating video.
- Director’s welcome
  The Institute of Theoretical and Computational Chemistry of the Universitat de Barcelona (IQTCUB) was created by the university Government Board on 27th November 2007 involving professors and researchers of different departments of the Faculties of Chemistry and Physics of the Universitat de Barcelona. Nowadays, also some groups of the Faculty of Pharmacy belong to the Institute. The common theme of the research projects conducted at the Institute is the use of methods that are rooted in quantum chemistry, recently it is also open to experimental groups of our Departments with deep collaborations with those focusing on computational chemistry. This should help to increase the multidisciplinary character of our research. Although traditionally the research at IQTCUB is mainly focused on chemistry, it is different from one would expect of a traditional chemist. Indeed, the common tools employed by the researchers at IQTCUB do not belong to a typical laboratory, but to a virtual computational “laboratory”. This “laboratory” is usually a gateway to our computational resources or to the supercomputing centers with even larger computacional facilities. The main goal of theoretical and computational chemistry is to achieve a detailed understanding of chemical and physical processes in order to assist in the interpretation…
- Direction team
  Direction team Prof. Eliseo Ruiz Sabin Director Prof. Jordi Poater Teixidor Secretary Prof. Iberio de P. Ribeiro Moreira Treasurer Prof. Francesc Illas i Riera Board Member
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- IQTCUB Annual Reports
  Here are of the annual IQTCUB activity reports that are available to download: IQTCUB report of 2018 ( CAT | ENG ) IQTCUB report of 2017 ( CAT | ENG ) IQTCUB report of 2016 ( CAT | ENG ) IQTCUB report of 2015 ( CAT | ENG ) IQTCUB report of 2014 ( CAT | ENG ) IQTCUB report of 2013 ( CAT | ENG ) IQTCUB report of 2012 ( CAT | ENG ) IQTCUB report of 2011 ( CAT ) IQTCUB report of 2010 ( CAT ) IQTCUB report of 2009 and 2008 ( CAT )
- XRQTC disseminating video
  You are welcome to see this video elaborated by XRQTC.This is a project done with the support of Direccio General de Recerca de la Generalitat de Catalunya through AGAUR. Authors: Xavier Gimenez (UB), Lourdes Vega (Matgas), Jean Didier Marechal (UAB).
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The IQTC is working in three main Research Areas and publishes 150 articles in the most prestigious international Journals
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The IQTC contributes to initiate chemistry undergraduate students to the discipline or to improve previous knowledge in Computational Chemistry
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Research Highlights

Home | Highlights 2014

Coupling of conformational and ionizatin equilibria in linear poly(ethylenimine): a study based on site binding/rotational isomeric state (SBRIS) model

Coupling of conformational and ionizatin equilibria in linear poly(ethylenimine): a study based on site binding/rotational isomeric state (SBRIS) model

J.L. Garcés, S. Madurga, M. Borkovec

Phys. Chem. Chem. Phys., 16 (2014) 4626.

2014-line3-a-250x200

Possible ionization and the conformational state of a linear polyethyleneimine (LPEI) oligomer with four amine groups. The conformation and charge distribution of the polyelectrolyte is treated at different levels.

The conformational and ionization properties of linear polyethylenimine are studied by combining the site binding model (SB) with the rotational isomeric state (RIS) model, developed by Flory to calculate the conformational properties of neutral linear molecules. The resulting approach (the SBRIS model) is used to rationalise the experimental polyethylenimine titration curves. By fitting the experimental macroconstants, conformational and binding parameters are obtained. The obtained values are consistent with previous binding and structural information. In order to account for excluded volume and long-range electrostatic interactions, Monte Carlo simulations are performed. The results indicate that at high ionic strengths, long-range interactions have a very limited impact on the titration curves. However, for long chains, they have a significant influence on the radius of gyration.