PCCP Blog

You can take a look at the excellent articles we have selected this week by clicking on the links below:

Waste to real energy: the first MFC powered mobile phone
Ioannis A. Ieropoulos, Pablo Ledezma, Andrew Stinchcombe, George Papaharalabos, Chris Melhuish and John Greenman  
DOI: 10.1039/C3CP52889H

Modulation of the stability of amyloidogenic precursors by anion binding strongly influences the rate of amyloid nucleation
David Ruzafa, Francisco Conejero-Lara and Bertrand Morel  
DOI: 10.1039/C3CP52313F

Electron transfer with azurin at Au–SAM junctions in contact with a protic ionic melt: impact of glassy dynamics
Dimitri E. Khoshtariya, Tina D. Dolidze, Tatyana Tretyakova, David H. Waldeck and Rudi van Eldik  
DOI: 10.1039/C3CP51896E

Stabilizing effect of electrostatic vs. aromatic interactions in diproline nucleated peptide β-hairpins
Kamlesh Madhusudan Makwana, Srinivasarao Raghothama and Radhakrishnan Mahalakshmi  
DOI: 10.1039/C3CP52770K

Accurate adsorption energies of small molecules on oxide surfaces: CO–MgO(001)
A. Daniel Boese and Joachim Sauer  
DOI: 10.1039/C3CP52321G

Solution-processed small molecule:fullerene bulk-heterojunction solar cells: impedance spectroscopy deduced bulk and interfacial limits to fill-factors
Antonio Guerrero, Stephen Loser, Germà Garcia-Belmonte, Carson J. Bruns, Jeremy Smith, Hiroyuki Miyauchi, Samuel I. Stupp, Juan Bisquert and Tobin J. Marks  
DOI: 10.1039/C3CP52363B

You can take a look at the excellent articles we have selected this week by clicking on the links below:

Interaction of electrolyte molecules with carbon materials of well-defined porosity: characterization by solid-state NMR spectroscopy
Lars Borchardt, Martin Oschatz, Silvia Paasch, Stefan Kaskel and Eike Brunner  
DOI: 10.1039/C3CP52283K
  

CuOx–TiO₂ junction: what is the active component for photocatalytic H₂ production?
Zhonglei Wang, Yuanxu Liu, David James Martin, Wendong Wang, Junwang Tang and Weixin Huang  
DOI: 10.1039/C3CP52496E

When I was perusing the ‘recently published’ pages for something to write about, I was moderately surprised to stumble on this article. It immediately caught my eye as being unlike anything I’d ever seen in PCCP before and I was curious.  My curiosity was well rewarded. Cardenas and Ayers have taken one of the more infamously qualitative principles of synthetic chemistry and relatively successfully attempted to quantify and assess its validity, something I have no doubt that the synthetic community will be thrilled to hear.

Although the broad concept of acid-base chemistry is familiar to anyone with a science GCSE, it’s more subtle nuances tend only to be revealed at a higher level. Acids and bases are described as having both a strength and an independent hardness, both of which are purely qualitative. Traditionally, strong acids and bases displace their weak counterparts, and hard acids and bases stick together. So far so good, but because these two traits are independent of one another, the two principles can sometimes be conflicting. Strong acids tend to be hard, and strong bases tend to be soft, but this does not always hold true.

Cardenas and Ayers characterise all acid-base reactions into four cases. In two of these, the hardness and strength principles reinforce each other, and in the other two they are opposed. They investigate which rule wins out in each case, and to what extent it dominates. Their findings are surprising and exciting, and could really have a serious impact as they provide a good deal of clarity to this issue. Reading this is highly recommended.

How reliable is the hard–soft acid–base principle? An assessment from numerical simulations of electron transfer energies
Carlos Cárdenas and Paul W. Ayers
Phys. Chem. Chem. Phys., 2013, 15, 13959-13968
DOI: 10.1039/C3CP51134K

by Victoria Wilton

You can take a look at the excellent articles we have selected this week by clicking on the links below:

Water and water-like liquids: relationships between structure, entropy and mobility
Divya Nayar and Charusita Chakravarty  
DOI: 10.1039/C3CP51114F

Self assembled materials: design strategies and drug delivery perspectives
Gunjan Verma and P. A. Hassan  
DOI: 10.1039/C3CP51207J

Resonance optical manipulation of nano-objects based on nonlinear optical response
Tetsuhiro Kudo and Hajime Ishihara  
DOI: 10.1039/C3CP51969D

You can take a look at the excellent articles we have selected this week by clicking on the links below:

¹⁴ N solid-state NMR: a sensitive probe of the local order in zeolites
Eddy Dib, Tzonka Mineva, Philippe Gaveau and Bruno Alonso
DOI: 10.1039/C3CP51845K

Manipulating spin hyper-polarization by means of adiabatic switching of a spin-locking RF-field

Alexey S. Kiryutin, Konstantin L. Ivanov, Alexandra V. Yurkovskaya, Hans-Martin Vieth and Nikita N. Lukzen
DOI: 10.1039/C3CP52061G

You can take a look at the excellent articles we have selected this week by clicking on the links below:

DNA photoreacts by nucleobase ring cleavage to form labile isocyanates
Laura Buschhaus, Josefin Rolf and Karl Kleinermanns   
DOI: 10.1039/C3CP51552D

Emerging applications of conjugated polymers in molecular imaging
Junwei Li, Jie Liu, Chen-Wei Wei, Bin Liu, Matthew O’Donnell and Xiaohu Gao   
DOI: 10.1039/C3CP51763B

Sensitized excited free-radical processes as read–write tools: impact on non-linear lithographic processes
Stefania Impellizzeri, Kevin G. Stamplecoskie and Juan. C. Scaiano  
DOI: 10.1039/C3CP51723C

Researchers in the group of Professor Martina Havenith at the Ruhr-University Bochum have shown that terahertz spectroscopy can be used, employing meticulous physical chemical considerations, to open a window into the solvation of ions in solution. In this paper they join the discussion regarding the solvation of trivalent lanthanide ions in water, by studying lanthanum chloride and bromide at different concentrations. They determine association constants for the ion pairs and investigate the nature of the lanthanide solvation—adding the experimental support to the proponents of outer-sphere interaction between anions and trivalent lanthanide ions in solution.

Sharma and co-workers investigate the ion pairing of lanthanum halides from a true physical chemical approach. A puritan approach that to me, make this paper a pivotal example of what a PCCP paper should be. Is should not necessarily following the most recent trend, but answer or address an important question. Here, the hydration of lanthanide ions. We do not know the structure of solvation lanthanide ions, even the stoichiometry is unknown. Except for an assumption that lanthanum has nine water molecules in the ligand sphere forming a symmetrical tricapped trigonal prism, the paper attacks the question of lanthanide solvation from a refreshingly new angle.

The image attached to this post shows how well terahertz spectroscopy can describe a solution of ions. Remembering that this image is generated from several layers of a priori information, such as the behavior of neat water, simple electrolytes, solutions of alkali halides etc. I strongly recommend that you read the paper is you are interested in the rare earths, electrolytes or specific ion effects.

by Dr Thomas Just Sørensen

Read this exciting PCCP article today:

From solvated ions to ion-pairing: a THz study of lanthanum(III) hydration
Vinay Sharma, Fabian Böhm, Michael Seitz, Gerhard Schwaab and Martina Havenith
Phys. Chem. Chem. Phys. 2013, 15, 8383-8391
DOI: 10.1039/C3CP50865J