CrystEngComm Blog

PbSe nanorods have been successfully made by solution–liquid–solid (SLS) growth of PbSe nanocrystals. This growth was followed by oriented attachment of adjacent PbSe nanoparticles. The team from South Korea who carried out this synthesis used Bi catalysts dispersed in the precursor solution to make these nanocrystals thereby reducing the time and temperature taken to produce them.

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Enhanced formation of PbSe nanorods via combined solution–liquid–solid growth and oriented attachment
Min-Seok Kim and Yun-Mo Sung
CrystEngComm, 2012, DOI: 10.1039/C2CE06353K

‘To get a polar crystal is still a challenging task,’ say Roberto Centore and colleagues. However in their CrystEngComm Hot article they in fact tell us about the discovery of a new class of non-chiral compounds forming polar crystal structures.

Their compounds are made by condensation of 4-hydroxybenzohydrazide with a variety of non-chiral aliphatic ketones, both cyclic and acyclic, such as methyl-ethylketone, acetone, cyclohexanone and cyclobutanone and all of them exhibit second harmonic generation (SHG) activity. In one case, they found that solid state polymorphism characterized by single-crystal-to-single-crystal transitions between polar phases was taking place.

Read their paper now – free to access until the 4th February:

A series of compounds forming polar crystals and showing single-crystal-to-single-crystal transitions between polar phases
Roberto Centore, Mojca Jazbinsek, Angela Tuzi, Antonio Roviello, Amedeo Capobianco and Andrea Peluso
CrystEngComm, 2012, DOI: 10.1039/C2CE06352B

The particular form a crystalline drug takes is highly relevant in the pharma industry as different crystal forms often have different properties such as dissolution rates or stabilities. Though crystallisation processes are commonplace in the production of enantiopure drugs, the way in which one enantiomer can affect the crystallisation of another has not be thoroughly studied.

In their recent CrystEngComm Hot Article, Munson and Berendt carry out such a study investigating proline enantiomers in a range of enantiomeric ratios. They determine that both the enantiomeric ratio and crystallization method influenced the polymorphism of the racemic cocrystal. Read how their work will have implications for current polymorphic screening methods used in the pharma industry in their article:

Effect of enantiomeric ratio and preparation method on proline crystal form
Robert T. Berendt and Eric J. Munson
CrystEngComm, 2012, DOI: 10.1039/C2CE06445F

With bacterial resistance to established broad-spectrum antibiotics on the increase, detailed understanding of antibacterial action and drug resistance mechanisms are urgently needed. This understanding enables success in structure based drug design of novel bacterial topoisomerase inhibitors. In their CrystEngComm paper Birger Dittrich and co-workers discuss why molecular electrostatic potentials are key for rational drug design. They look at the optimization of structures on the basis of a comparison of nine fluoroquinolone antibiotics.

Electrostatic properties of nine fluoroquinolone antibiotics derived directly from their crystal structure refinements
Julian Jacob Holstein, Christian Bertram Hübschle and Birger Dittrich
CrystEngComm, 2012, DOI: 10.1039/C1CE05966A

In their CrystEngComm Hot Article, Hirohito Tsue and colleagues from Kyoto University, demonstrate crystallographic evidence of trapped volatile gases in an azacalixarene structure. The paper looks at the solid–gas sorption behaviors of azacalixarenes at low temperatures among five gases, N₂, O₂, Ar, CO₂, and CH₄.

 Why not read Tsue’s study for free until 16th December……..

Crystallographic analysis of CO2 sorption state in seemingly nonporous molecular crystal of azacalix[4]arene tetramethyl ether exhibiting highly selective CO2 uptake
Hirohito Tsue, Hiroki Takahashi, Koichi Ishibashi, Rikako Inoue, Shun Shimizu, Daisuke Takahashi and Rui Tamura
CrystEngComm, 2012, DOI: 10.1039/C1CE06126G

In their recent CrystEngComm paper, Zhimao Yang and co-workers from Xi’an Jiaotong University in China, tell us about the cubic CuS cages they have synthesised. These cubic cages (see image below) form high-activity nanotwinned building blocks. The group also study the significance of these copper sulfide nanotwinned structures for enhancing the catalytic degradation of methylene blue (MB). Read more in the article below – free to access until the 2nd December.

Copper sulfide cages wholly exposed with nanotwinned building blocks
Shaodong Sun, Xiaoping Song, Chuncai Kong, Dongchu Deng and Zhimao Yang
CrystEngComm, 2012, DOI: 10.1039/C1CE06135F

In their recent CrystEngComm Hot Article, Xutang Tao and colleagues report the successful growth of bulk α-BaTe-Mo₂O₉ polar single crystals using a top-seeded solution growth method. The search for new polar materials is of current interest owing to their potentially important functional properties including piezoelectricity, pyroelectricity, ferroelectricity and secondharmonic generation activity.Indeed these large crystals offer a promising candidate for optical devices such as light modulators, colour filters, wave plates and
optical axis gratings. Find out more about this polar polymorph by reading the article – free to access until 24 November 2011.

Bulk crystal growth and characterization of a new polar polymorph of BaTeMo₂O₉: α-BaTeMo₂O₉
Junjie Zhang, Zhonghan Zhang, Youxuan Sun, Chengqian Zhang and Xutang Tao
CrystEngComm, 2011, DOI: 10.1039/C1CE05922J