# Theoretical graphene question

Let’s say I have a sheet of 1 atom thick graphene. If I press my finger down on it’s edge does it cut right through my finger?

I’d elaborate, but I think the question (as a hypothetical) stands on it’s own.

A sheet of 1 atom thick graphene is secured in a device vertically. Downward force is applied in the same way a finger presses a button.

Some physics and perhaps chemistry would dictate what happens, right?

Since you have not gotten an answer, I will posit a guess based on what little I know. I would guess that the graphene would not be strong enough to remain in place. It is the resistance to movement that allows a collision to deform an object, and I would guess that the atoms in your hand would have a greater resistance to movement than any single atom thick substance.

I would guess that BigT is right, and the graphene will simply tear. However, if the strength of graphene should turn out to be much greater than either of us think, then it will slice into into your finger, just like a sharp metal blade would in similar circumstances. There is nothing particularly special, in this scenario, about the fact that it is a monolayer. It just means that it would be a very sharp edge (if it held together).

However, given that flakes of graphene rub off graphite all the time, and don’t seem to cut people up, I am reasonably confident that graphene does not, in fact, present any significant danger.

Also, what’s affixing the graphene in place as you bring your finger down upon its edge vertically? Perhaps your finger would just push the graphene out from whatever is holding it.

I would expect that the graphene would crumple before it would tear, as it’s quite flexible.

Right; wouldn’t it just bend as your finger came down on it? A sheet of aluminum as thick as a soda can wall will cut your finger in such a circumstance, but a sheet of aluminum as thick as common kitchen foil will simply bend and crumple as it encounters your finger.

As I read the OP, we are to assume that it is firmly held in place, presumably stretched between two clamps of some sort. Under those circumstances I don’t see how it would crumple (unless is is stretchy stuff, which I doubt).

This just came out of Harvard: http://youtu.be/EzmmgWSyeRw

Make your on graphene–yup, 1 atom thick using scotch tape and a flake of graphite.

1. So how do they know, in the real-time activity shown, that the resulting layer includes a layer of graphene?

2. Can I do that with other available stuff–one-atom thick, ta-da!..? with anything.?(Assuming I have a clean-box at home).

Do I/us come into contact (not literally) – interact with – any 1-atom-thick uniquely identifiable functional portions of physical objects in our lives? I’m thinking, eg, “the [insert name] layer of [insert biological structure, of people/plants/amoebae] is a layer 1-atom thick…”

I suppose there are singleton atoms floating around, so by definition they’re out there.

Pretty mind blowing. That and gravity waves for my big week.

Technically, you probably come across free-floating single atoms of carbon from time to time; I’m assuming hydrogen, oxygen and nitrogen (which you also run into) don’t count as solids.

Layers one molecule thick are common - Langmuir monolayers are organic molecules assembled on a liquid surface, and can be deposited onto a solid surface in Langmuir-Blodgett films.
These are a big deal in biology, as they’re used to address the question of compartmentalisation - how biological membranes, micelles and vesicles work in the cell.

If you’re specifically interested in monolayers of atoms then I can’t think of any off-hand in the biological sphere - it seems like something that is necessarily inorganic. There may be examples in materials where you can deposit a monolayer of an elemental metal onto a solid substrate.

Everything is stretchy stuff to at least some degree, and the situation as described (pushing at a right angle on something held taut) provides an incredible amount of mechanical advantage. It’d be almost guaranteed to crumple to at least some degree, and I’d be quite surprised if it didn’t crumple enough to blunt the edge.