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Porous materials, minerals and bees

Thoughtful and very well written. Nice analogy with the bees!

Molecular Dreams

Overwhelmed with the increasing flow of new scientific discoveries and related literature? You’re not alone. We live in the information overload era: too much to read, too little time, and life is short. Probably we’d need more readable, shorter papers too. Why writing a long one? Perhaps, it might connect disciplines which speak different languages but have much in common. Like material science and mineral science.

Let’s start from the first one.

You can make materials for solar cells, optical devices or medical sensors by trapping molecules or nanoparticles inside a “host”. Once there, molecules are no longer free to move, like in a gas or a liquid.  This process, called “confinement”, brings to life new properties, which were not present in the individual molecules and are very useful in technology.  Energy transfer or information storage, for instance, are made possible by the organization of the confined molecules

P1270522 The…

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230@CrystalWorks – The space group list project (update)

We are happy to announce that the space group list project is now completely accessible and incorporated into CrystalWorks.

CrystalWorks is part of the National Chemical Database Service (CDS) of the Royal Society of Chemistry (UK) and comprises crystallographic data of organic (CSD), inorganic (ICSD), and metallic (CrystMet) compounds.

The CrystalWorks link on this page provide full display functionality for all 230 structures. In particular full interactive structure display is available via JSmol (see screenshot below). This provides useful features which are complementary to those of VESTA.

screenshot_crystalworks

Chapter 5 activated!

Dear Students,

today Chapter 5 of our course has been activated!

We hope, you are all doing well!

In this week we will practise the handling with the International Tables a little further. But in contrast to staring only at circles and commas we will additionally look at real world crystals and some of their symmetry and physical properties. And you can be curious about the story of one of the most thrilling scientific discoveries of the last century: the discovery of quasicrystals by Dan Shechtman.

Looking forward to meet you at class and in the forum!

Frank and Michael

Announcement_10-fold_chapter_5

#196 – update

#196 – update

F23

Tomas, one of our readers of this blog, identified an error concerning the space group list project. As he correctly pointed out, the entry of #196 (F23) was wrong as the coordinate set of the solvent free zink  sulfate clearly shows F-43m symmetry (#216).

I have informed the FIZ Karlsruhe and they will delete this wrong entry in their ICSD database with the next update/release.

So, the new (approved) entry for #196 is:
tetrakis((18-Crown-6)-thallium) tetrachloro-manganese bis(tetrachloro-thallium)
Coordination Characteristics of Divalent Tetrahedral (Td and D2d) Tetrahalometalate Anions of 3d Elements and Solid-State 18C6 Reorientations
N.S. Fender, S.S. Finegan, D. Miller. M. Mitchell, I.A. Kahwa, F.R. Fronczek
Inorg. Chem., 1994, 33 (18), pp 4002–4008

http://dx.doi.org/10.1021/ic00096a026
CIF
http://1drv.ms/1nJuoOs

HEWMOL
MnCl4 tetrahedra (purple)
TlCl4 tetrahedra (blue)
https://skfb.ly/BuHu

 

Also the poster of the Space group list project was updated, which you can download here:

https://crystalsymmetry.wordpress.com/2014/08/15/the-space-group-list-project-as-a-poster/

Chapter 6 starts today!

Dear Students,

in this week we will introduce a very special class of crystalline materials, which are called Metal-Organic Frameworks or short MOFs. Research interest in this kind of materials has intensified immensely over the last decade. As MOFs are also the field of study of our research group, telling you something about these very special crystals is a matter of heart for us.

MOFs are comprised of inorganic and organic secondary building units. We will take a look at different variations of how these secondary building units can be assembled together and we will introduce the principles of classification of these network-like assemblies.

We provide several crystal structures of MOFs as VESTA files, in order for you to be able to get familiar with the structural features of MOFs at the atomic level. (You can find a tutorial on how to obtain and install VESTA in Unit 2.7)

At the end of this chapter we will be prepared for the next week, in which we will introduce software (called TOPOS and Systre) that allows investigating, determining and classifying the topology of Metal-Organic Frameworks in a systematic way, i.e. to answer the question what are the underlying nets (= linked vertices) and how can we precisely describe them?

Enjoy the beauty of porous crystals!
Michael and Frank

Announcement_maze_chapter_6

Get ready for Chapter 5!

today at 12:00 p.m. (noon in Berlin) Chapter 5 of our course will be activated.

We hope, you are all doing well!

After the halftime break, we will practise the handling with the International Tables a little further. But in contrast to staring only at circles and commas we will additionally look at real world crystals and some of their symmetry and physical properties. And you can be curious about the story of one of the most thrilling scientific discoveries of the last century: the discovery of quasicrystals by Dan Shechtman.

Maybe some of you are also willing to contribute to the growing list of one concrete example of a crystal for each of the 230 space groups? Have a look at:

https://iversity.org/my/courses/the-fascination-of-crystals-and-symmetry/discussions/43529

Looking forward to meet you at class and in the forum!

Michael and Frank

Announcement_10-fold_chapter_5