It is finally spring break here for Uni Melbourne students! I am going on a short trip with another American girl to Tasmania, so I'll be offline until I get back on Wednesday night. Until then, I'll leave you with these cool pictures I took today through the microscope. The cool, but unfortunate, thing about the bottom picture is that the crystals I wanted were mixed in with excess ligand that had come out of solution and crystallized. This sample was intended for elemental analysis, so I spent a lot of time on the microscope trying to separate the clear ligand from the blue complex to avoid a biased result from the analysis.

Diamond network crystals.

Stacked sheet crystals (NO3 counter ions) mixed with crystallized ligand. There is also a fiber in the top right corner from the filter paper I used to collect the crystals.

Stephanie

Sheet structure

As I promised, here's the sheet structure I just made!

At the top left is a bird's eye view of a single sheet. At the top right corner is two sheets layered above each other. From this view you can see that the sheets do not stack directly on top of each other in an AAA... fashion; they actually stack in an ABAB... manner. At the bottom left, I have just rotated the the top right picture so you can see the sheets from the side. At the bottom right, I have added more sheets (the other pictures have sheets removed for clarity) so that the ABAB... pattern is more obvious.

As chemical research project comes to a close, I've spent this last week in lab tying up loose ends rather than trying to find more structures. I have taken some nice IR spectra that confirm the presence of certain functional groups (like C=O and NO3) in the crystals. Other than that, I am getting things together for my final report and project talk.

Stephanie

Good news everyone!

So far I have been trying a lot of different metal base combinations in the hopes of getting another interpenetrating network or some kind of unique structure…all to NO AVAIL. More recently, I have been using a variation of a variation of DABCO (which looks like this http://en.wikipedia.org/wiki/DABCO), which I mentioned in an earlier post, and I finally got a good hit!

GOOD NEWS EVERYONE! Chemistry works! …as Professor Farnsworth (from Futurama) would say.

The crystals I have are still derived from copper; the other metals I have tried still haven’t worked so well.  Actually, they are the same color as the 4-interpenetrating network, so I thought at first the crystal structure would be the same. Below you see the crystals from the quadruple interpenetrating network.

It turns out that the new crystals form stacked sheets in an ABAB… fashion. Cool!!! You can see my vials below! Interestingly the sheets have different sized holes as well.

It was super exciting to get these results because Chemical Research Project is coming to a close soon. In fact, we have our presentations in about 2 weeks! I don’t have a nice picture to show you yet of the actual sheets (ie. a crystal structure), but I’ll post it when I have it ready!

Stephanie

So far things in lab have been going pretty smoothly. For the past few weeks I have been using a variation of DABCO. DABCO stands for 1,4-Diazabicyclo[2.2.2]octane and looks like this...

It is with this variation that I made the interpenetrating diamond-like network. It seems as though trying to recreate the network using different metals hasn't been very effective, so now I've moved on to playing around with 1) the network itself and 2) another variation of the DABCO ligand.

1. As I have mentioned before, the network is very spacious! I recently set up a few experiments to see what kind of atoms and molecules we could put in the network. When I make the network, chloride ions sit within the spaces. The Cl ions come from the variation of the DABCO ligand, which uses Cl as an ion to balance out positive charges that reside on the nitrogens.

2. The second variation of the ligand uses different counter ions. Instead of Cl ions, it uses NO3 ions. I have just set up a lot of new solutions with different metals in hopes that this different ligand will get us some interesting crystals.

My other classes seem to be going well too. It has been a very busy time again because our mid-semester break is coming up (even though it is past the mid-semester)! I have planned a short 4 day trip to Tasmania, so I'm really excited for that! I'll keep you updated!

Stephanie

A nice break from work

I met up with my friend Stacy at around noon at Federation Square. We originally were planning on going to the NGV (National Gallery of Victoria), but it was such a beautiful day out that we ended up walking around the botanical gardens a bit.  The beautiful pink tulips convinced us it was a much better idea to stay outside!

Stacy mentioned that the Shrine of Remembrance was in the direction were headed, so we decided to check it out. We found a few other spots that were also really beautiful on our way there!

Finally, Stacy and I arrived at the Shrine of Remembrance, which originally commemorated WWI veterans, but now serves as a memorial for all Australians who have served.

View from the top of the memorial.

It was nice to walk around on such beautiful day outside and take a little break from work! 

Stephanie

Lab life

We are starting week 8 next week already and there are only 3 more weeks left until my project wraps up! Everything is moving so quickly!  Since getting the diamond-like structure I mentioned in a previous post, I have been trying to get a similar structure using other metals. More recently I've been using some lanthanides...like neodymium, samarium, gadolinium, etc. I haven't gotten anything super exciting recently, so I'll just leave it at that.

It has been great interacting with people in the group though. There are no formal group meetings like back at home; everything seems to be a lot more casual. Professor Abrahams will drop by in lab usually once or twice a week to ask people how their projects are going and chat a bit. 

Two members of the group just returned from holiday, Jess and Keith. Jess is working on her thesis and Keith is a postdoc (actually my project started as an extension of his thesis work).  It was nice to finally have another girl around the lab and Jess is really friendly! She invited me to go out for drinks with her and some of the other grad students/master's students/postdocs. She bought me some cider and said when she was doing Chemical Research Project, other grad students had bought drinks for her! It was really nice and reminded me a lot of summer group outings at the Athenaeum. 

The group also does this daily thing at around 4 pm called "Tea Time". Essentially people gather in the kitchen/common area for 20ish minutes and go over a daily trivia quiz from one of the newspapers. After, someone describes the Fred Basset comic strip and everyone tries to guess what the last panel of the comic says. 

Everyone is just really nice and friendly! It's great to be working in lab and have lab mates who make the experience even better!

Stephanie

Lab results!

Even though it was awful being sick, when I went back to lab I had some really nice results! The crystals I had been getting before had been making long stacked chains, which although that's still cool, wasn't really what Tim and Prof. Abrahams had  been hoping to see. Fortunately for me, one of the crystallizations I set up yielded some really nice blue copper crystals that had a completely novel structure! We describe it as a having 4 interpenetrating diamond networks.

A diamond network is made up of adamantane units. http://en.wikipedia.org/wiki/File:Diamondoids.png In 1, you see one unit and, in 2-4, you see the addition of successive units. Because of the ligand and metal I used, the diamond-like network has a lot of space in it. As a result, we can put things in this excess space. In the case of my crystals, one of the networks will interpenetrate 3 more identical diamond-like networks in this space. In the picture below, each color represents a single, individual network. Each network is made up of carbon, nitrogen, oxygen, copper, and hydrogen.

The four identical, interpenetrating diamond-like networks.

I've omitted the other 3 networks for clarity and tried to illustrate the single adamantane unit in white.

I have been trying to set up variations of this in hopes of getting similar kinds of results with other metals. Hopefully I'll have something nice after the weekend!

Stephanie

Oh no, sick!

Unfortunately, I've come down with something awful and was sick the whole weekend! I made it to the health center today, but was told by the doctor not to attend class for 3 days because I am contagious! Hopefully I'll have some interesting updates for you by the end of the week. Until then, I'm going to get a lot of needed zzz's.

Stephanie