Picture it…

Chemistry

Crochet Enantiomers

4 Comments

photo of crochet molecules
A pair of crochet enantiomers.

Since re-learning how to crochet (I kind of knew as a teenager, but didn’t pick it up again until 2014), I’ve made a few crochet molecules, mostly as presents for the kids of scientists and for outreach workshops. Some people have asked for patterns and while there is not much to it, I’ve begun to write some of them up, starting with a quick and easy one, which is made up of a central sphere, surrounded by 4 smaller spheres, all made using the amigurumi method.

For the chemists among you, it’s a chiral carbon centre, which just cries out for its enantiomeric sibling. The following pattern will make one, simply repeat to make a second one, and be careful that you make it an enantiomer (non-superimposable mirror image) when you assemble it.

Crochet spheres/atoms made.
1 large and 4 small atoms ready to go.

Pattern uses UK terms and follows the amigurumi method, i.e. working in a continuous round. You might find it easier to use a stitch marker or small bit of yarn to mark each round. The molecules shown here are made in Aran cotton yarn, but any yarn will do (I find 4 ply gets fiddly, though). Use the smaller hook size given on the yarn band, or an even smaller hook depending on your tension; you don’t want any gaps. Depending on how stiff the cotton yarn is, I would use a 3.5 or 4 mm hook with Aran cotton yarn. Atoms are stuffed with toy stuffing, made from recycled plastic if you can get it.

Stitches used: dc – double crochet, MR – magic ring, incr – increase, invdecr – invisible decrease. Planet June is good if you need a tutorial.

Large crochet sphere.

Large, central atom (make one, optional 6 mm toy safety eyes, only suitable for children older than 3 years.)

See comments for a couple of tweaks.

1. Start with a magic ring. 6 dc into ring and close. (6)

2. 6 Incr. (12)

3. (Incr, 1 dc) x 6. (18)

4. (Incr, 2 dc) x 6. (24)

5. (Incr, 3 dc) x 6. (30)

6. (Incr, 4 dc) x 6. (36)

7. (Incr, 5 dc) x 6. (42)

8-12. Dc around. (42) Repeat 4 more times. Insert toy eyes between rows 9 and 10, 6 dc apart or to taste, fasten backing plate safely.(Invdecr, 5 dc) x 6. (36)

13. (Invdecr, 4 dc) x 6. (30)

14. (Invdecr, 3 dc) x 6. (24)

15. (Invdecr, 2 dc) x 6. (18) Start stuffing.

16. (Invdecr, 1 dc) x 6. (12) Stuff to desired level.

17. (Invdecr) x 6. (6) Fasten off, leaving a tail for sewing.

Using a blunt yarn needle, close the remaining gap by weaving your yarn tail through front loops only and pulling tight. Weave through the end to secure and hide yarn inside your atom. If you tension it slightly when you snip off the remaining tail, it will disappear inside.

Small crochet spheres/atoms

Small atoms (need 4, in 4 different colours if making chiral molecule)

1. Start with a magic ring. 6 dc into ring and close. (6)

2. 6 Incr. (12)

3. (Incr, 1 dc) x 6. (18)

4-6. Dc around. (18)

7. (Invdecr, 1 dc) x 6. (12) Stuff to desired level.

8. (Invdecr) x 6. (6) Fasten off, leaving a long tail for sewing.

Using a blunt yarn needle, sew the first small atom over the final round of your large atom, then fasten off the yarn end and hide it inside.

Sew the other 3 small atoms around the bottom of your large atom. They should be evenly spaced to form a tripod. I’ve arranged mine so they frame the toy eyes and attached them so their outside sits on row 5.

Ideally, the angle between the small atoms is 109.5 degrees; just getting a pleasing arrangement is good enough.

If you make a second molecule, switch two of the small atoms to make non-superimposable mirror images. This is a property of molecules called chirality and you can read more about it here.

Completed enantiomers!

Natalie Fey

4 thoughts on “Crochet Enantiomers

  1. These are adorable! Part of me is tempted to go get some yarn and try crocheting as I also did a little when I was younger. But then again, every scarf I tried making ended up becoming a Barbie blanket for little sister because I didn’t have the attention span so maybe I will just send this pattern to my friend instead. 😀

  2. Hi Natalie, this is such a good and simple idea that I would have loved to have had it myself. I started making a pair last night! I do have two comments though: I think the middle section of the large atom needs two more rounds of dc around, as with the pattern you describe it does not really come out as a sphere. In other patterns I have, the rule of thumb is to have roughly as many ‘straight’ rounds in the middle section as increases in the first and decreases in the final section, in order to achieve something roughly spherical.
    The other comment is that I can thoroughly recommend staggering the increases rather than having them all line up. I tend to do that by alternating increases at the beginning (or end) and middle of each repeated set, i.e. round 4 I would replace with (dc, inc, dc)*6 and round 6 I would replace with (2dc, inc, 2dc)*6. I hope this makes sense. Happy crocheting!

    • Hi Maria, thanks for pattern testing!
      If I’m getting my counting right, the purple ones you can see in the background are a bit smaller and have the extra rows making them rounder. I quite like the rakish look of the more squashy ones, especially with the toy eyes, though.
      Either that, or I could blame relativistic effects, but the contraction wouldn’t just be along one axis.
      And thank you for suggesting staggering the increases, that will make them a bit neater and I’ve added a note to the pattern to look at the comment. You are going to love this one: https://www.ravelry.com/patterns/library/ideal-sphere.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s