## Sunday, March 28, 2010

### One more beaded rhombic triacontahedron

It is very easy to make rhombic triacontahedron. I made one more using different kind of beads.

### Rhombic triacontahedron

I created this beaded model of rhombic triacontahedron this morning.

## Thursday, March 25, 2010

### C1500 in the preparatory problem of IChO 2010

Problem 3 in the preparatory problem of IChO 2010 asks the buoyancy property of icosahedral buckyballs. It would be interesting but time consuming to construct all beaded models for the buckyballs with I symmetry less than 1500 carbon atoms. Right now, the largest buckyball belonging to this family I made is C320.

This problem claims that the giant buckyball are molecular balloons.
To me, the Archimedean principle of buoyancy is a macroscopic law due to the pressure course-graining over large amount of tiny collisions. Nano-particles such as C1500 have sizes less than the mean free path of the gas at 1 bar. So these nano-particles should simply follow the Boltzmann distribution, P ~ exp(-mgh/kT), based on their potential energy, mgh, at the height.

### C320

I made this large icosahedral buckyball with 320 carbon atoms last night:

### 台大化學營 (Winter camp for High school students at Chemistry department of NTU) 20100204

Here are some pictures from a talk I gave in the winter chemistry camp for high school students last month (Feb. 4, 2010) here at chemistry department of National Taiwan University. Right after the talk, there was a workshop for students to construct bead model of C60. We have many undergrad assistants to help them to make the beaded buckyball.

My experience of workshop on beaded fullerene is to give a one-hour talk on the background of fullerenes, chemistry, geometry and then give a small exhibition about the beadwork we have created. Then we can have a workshop for students to create simple object such as C20, C60, C70 and so on. Creaction of other topologically nontrivial structures such as high-genus fullerenes, periodical minimial surfaces etc. are time-consuming. So I don't think it is possible to make them in a short time. One needs patient to make them.

updated May 28, 2010

## Saturday, March 6, 2010

I found these two beaded mice at the brother's place in the Chinese new year eve.

### IQ ball (Dodecahedral paper ball)

I got this "IQ ball" as a gift from my sister-in-law. It took me about 20 mins to assemble it in one of Starbucks outside the main campus of NTU.

### Two more pictures for the Sierpinski buckyball

This Sierpinski buckyball is currently at the chemistry departmental office of NTU.

### More pictures

Some more pictures I took at 新光三越. I had two beaded models with me that day (Second day of the Chinese new year, 大年初二).

### Icosahedral paper ball

I found this in "Xin-Guang-Shan-Yuan" XinYi region of Taipei city.