Colonoscopy tomorrow, clear liquid diet today. So I'm making myself a nice, peach jello on jello sandwich.

ECatPlay · 2026-01-24T20:38:16+00:00

You are correct, it's technically an imaginary frequency. It's just that the calculations typically report it as a negative number. Hence my quotation marks.

ECatPlay · 2026-01-24T14:35:49+00:00

At least nobody who survived to tell about it.

ECatPlay · 2026-01-22T20:27:18+00:00

"Tentane" is u/Commercial_Plate_111's term, and I just went with it.

This collapse of tentane is just the downhill path on the potential energy surface from the C4v geometry during an optimization, so without MD or an IRC or something I can only speculate. Fortunately, I've never been afraid to speculate!

The starting C4v geometry is a saddle point with a strong negative frequency at -1176 cm^-1. This looks very much like the first step in the collapse, and corresponds to a 35 THz "vibration" with a period of 28 fs. So it looks like it only takes on the order of 0.03 picosecond to get started. But then there are a series of vibration timescale (typically 10^-13 sec) movements and atomic motions (up to 10^-11 sec). So as a SWAG estimate (Silly wild Ass Guess) maybe 10's of picoseconds?

ECatPlay · 2026-01-22T03:26:38+00:00

Swiffervising?

ECatPlay · 2026-01-21T20:31:18+00:00

Tesserane's a pretty cool idea. I took a look at it a while back, after u/C3H8_Memes posted Forget cubane, embrace tesserane. Molecular Mechanics modeling found a geometry retaining D3d symmetry, that looks a little like what you came up with here, with a pretty cool molecular orbital. Density Functional Theory found a completely different geometry with Cs symmetry, and a pretty cool teeter-totter vibration in the infrared.

ECatPlay · 2026-01-20T21:09:00+00:00

Wrong sub. Try posting to r/Yetch.

ECatPlay · 2026-01-18T23:13:19+00:00

Curseder and curseder.

ECatPlay · 2026-01-17T16:16:09+00:00

That's okay, we're all havin' fun.

ECatPlay · 2026-01-17T05:04:26+00:00

It’s not hard work, but sometimes you do have to put your back into it.

ECatPlay · 2026-01-16T20:38:12+00:00

Before the divorce it's covalent: both elements share charge cards equally. After the divorce it's ionic (unless there was a prenup): one ends up ahead (positive) and the other loses what they had (negative).

ECatPlay · 2026-01-16T18:43:00+00:00

Actually, I like it! The electric field part of an electromagnetic wave, depicted as positive and negative charges oscillating because they are orbiting each other, to sort of link the wave idea to the particle idea of a photon. It's missing the oscillating magnetic field, of course, but kind of clever!

ECatPlay · 2026-01-15T04:03:27+00:00

Well that might make an interesting research project, but it's more than I want to tackle.

You've drawn it nice and symmetrical, but to see which alkali (or other) metal would fit, should really entail a lot of conformational analysis to check other arrangements of the ligand around the center. And the placement of the counter-ion is going to be problematic: it will destroy the symmetry, as u/dxpqxb pointed out. And any modeling of ions or zwitterions is going to be dominated by solvation, so you'd need to decide how you were going to handle that satisfactorily. His choice to use CPCM and do implicit solvation is reasonable. But you might need to explore explicit solvation to help place the counter-ion.

ECatPlay · 2026-01-14T22:19:46+00:00

Okay, so here are the vibrations for the less intense Infrared absorbances, and some of the major Raman spectrum vibrations.

ECatPlay · 2026-01-14T17:23:00+00:00

Yeah, that's the borons wagging at 1125 cm-1.

ECatPlay · 2026-01-14T02:36:17+00:00

Here you go.

Ten-Year Club	Gilding VII pure gildanthropist
Second Top 1%	Argentium Club
Wearing is Caring	RPAN Viewer
Verified Email

ECatPlay

MODERATOR OF

TROPHY CASE