Advertisement
Grab your lab coat. Let's get started
Welcome!
Welcome!
Create an account below to get 6 C&EN articles per month, receive newsletters and more - all free.
It seems this is your first time logging in online. Please enter the following information to continue.
As an ACS member you automatically get access to this site. All we need is few more details to create your reading experience.
Not you? Sign in with a different account.
Not you? Sign in with a different account.
ERROR 1
ERROR 1
ERROR 2
ERROR 2
ERROR 2
ERROR 2
ERROR 2
Password and Confirm password must match.
If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)
ERROR 2
ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.
Synthesis
Chemistry In Pictures
Chemistry in Pictures: Vapor diffusion
by Craig Bettenhausen
February 18, 2020
Tiffany Poynder had a nice surprise waiting for her in lab one recent Monday morning—crystals! Getting good crystals is always satisfying, and suggests that the compound in the vial is pure. But they’re crucial for Poynder, whose research is on perflourinated molecules that are difficult to isolate and characterize. Having nicely formed crystals to work with enabled her to use X-ray crystallography to identify what she had.
The crystallization setup shown in the photo is a classic called vapor diffusion. The molecule of interest is dissolved in a solvent or solvent mixture in the inner vial, which is left open. Then a different solvent, one that doesn’t dissolve the molecule well, goes around it in the outer vial, which is then capped tightly. Vapors of the outer solvent slowly mix in with the inner solvent (and vice versa), making the solvent in the inner vial less and less hospitable. Eventually the molecule can’t stay in solution, so it (hopefully) comes out as crystals.
Credit: Tiffany Poynder, @tiffany_poynder. Read more from this research: (Chem.–Eur. J. 2019, DOI: 10.1002/chem.201806110)
Do science. Take pictures. Win money. Enter our photo contest here.
Related C&EN Content:
You might also like...
The power is now in your (nitrile gloved) hands
Sign up for a free account to get more articles. Or choose the ACS option that’s right for you.
Already have an ACS ID? Log in
Join the conversation
Contact the reporter
Submit a Letter to the Editor for publication
Engage with us on Twitter