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wave function molecular modeling

modeling molecules as wave functions rather than marbles
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By now we're all familiar with the marble-kit molecule models, where each element is a round ball with a number of holes in it. You build a molecule by connecting sticks between different atoms. Sort of the 'erector set' of physics.

However, atoms can also be described as waves. It would be cool to see an image of a molecule as an interaction of the various wave functions of the atoms.

lawpoop, Dec 02 2008

Hydrogen Density Plots http://en.wikipedia...n_Density_Plots.png
Ths is what I'm talking about, only instead of a single atom, it would be all the atoms in a molecule. [lawpoop, Dec 02 2008]

A startt, but still has marbles http://dcwww.camd.d...po/examples/vtk.gif
This drawing shows some waviness in the molecule, but it still has two marbles in it. It's a start. [lawpoop, Dec 03 2008]

[link]






       Complex molecules like proteins are often represented as electron density maps or as 3D electronic surfaces (being the boundary of the molecule at a specified electron density).   

       The most beautiful were those made in the early days of X- ray crystallography, where the density contours were plotted on sheets of glass which were then stacked to give a 3D representation of the molecule.
MaxwellBuchanan, Dec 02 2008
  

       so "translate the un-toyness of the subatomic world into an easy to grasp toy-like format". Not sure if that is less, or more, challenging than it sounds. I like it, however.
WcW, Dec 03 2008
  

       [WcW] Well, it's sort of already been done. You've played with the molecule building kits, right? That seems to have gone okay.   

       If you can make drawing of hydrogen atoms like the one linked, why couldn't you make a similar drawing of a whole molecule?
lawpoop, Dec 03 2008
  

       yes, the Tinkertoy model is very handy. Problems really start when we go down to the subatomic level and nothing is behaving like it should. Furthermore since we are using a simile, waves, to describe a behavior that is not literally a wave in the classical sense and thus cannot be depicted as a line or as a probability field in the traditional sense we really fundamentally lack the tools to depict the subatomic world. I guess i would say that trying to draw something that is inherently not visual and follows none of the visual rules that we use every day presents a real artistic and educational challenge. So extreme are the problems presented that sound or touch might be easier mediums. This is why quantum physicists end up using so much math, other tools of depiction just fall flat.
WcW, Dec 03 2008
  

       Quantum waveforms are a step away from their corresponding probability fields. If anyone has ever cared to do the math. I think relating them is fine.
daseva, Dec 03 2008
  

       [WcW]   

       1. What problems do you think exist with the Hydrogen Density Plots linked? Could that not be expanded to a molecule   

       2. Some of your criticisms talk about the fact that atoms are not really waves. But they're not really particles, either. So if the tinkertoy particle model is handy, then why wouldn't a wave depiction also be handy? Both would be not 100% completely accurate simplifications, but perhaps useful for depicting certain aspects of the wave/particle duality.
lawpoop, Dec 03 2008
  

       I suspect that to go deeper into the subatomic realm we must discard the traditional notion that mater is made up of materials akin to the materials that we can perceive. The electron "orbital" such as your link depicts are a classic example of trying to depict this. We want to presume that electrons are tiny little baseballs when they are moving and blobbie "zones of probability" when they are at rest when in-fact Schrödinger observed that they never exist in either state until we "catch" them. This is the duality. It is only a paradox if you try to force the electron or other subatomic particle into the visual and physical rules of our world. On the other hand if we accept that this is impossible and that the subatomic world is a window into the structure of the universe and that all aspects of that structure are normally completely hidden to us because we are looking from the inside of the box we start to get somewhere.   

       Models are good for making predictions. The reason why we don't have diagrams for anything but H is that we don't have the data yet so we can't make very good predictions about how electrons are behaving in larger atoms.   

       I believe that the duality question is a red herring, on a subatomic scale particles follow rules that have no corollary in the macro world and thus cannot be drawn.   

       I don't understand what you want if the link satisfies you. I personally think that the discovery of electron behavior was to humanity as a baby's fist step is to an Olympic gold medal in the triathlon. We have a long way to go yet.
WcW, Dec 04 2008
  

       The whole Quantum Wavicle thing is applicable only to sub-atomic particles, which may or may not exist as probablistic pseudo-entties.   

       However, if you take te trouble to study molecules (composed of atoms, which arethemseves composed of sub-atomic partcles) you will quickly realise that they actually do look like litte coloured snooker balls held to one another by bits of cocktail stick .....
8th of 7, Dec 04 2008
  

       I'm guessing that you are making a joke....
WcW, Dec 05 2008
  

       I like to believe - ultimately, there is a volume that is truely empty called nothing. if this 'space' is filled, the stuff is called matter. All the rest is just patterns, motions, perspectives and, of course, measurement .   

       disclaimers (1) quicky sidesteps higher dimensions as a reality . (2) The inverse idea that everything is solid and we are spaces moving in the block is still there . (3) Oh, and reality has analogue motion which is a problem for mathematics .   

       Modelling there and not there is a good start . The ball and stick is just a trimmed down, simplified probability model anyway .
wjt, Dec 05 2008
  

       sadly the science seems to indicate otherwise.
WcW, Dec 05 2008
  

       But if the simulation crashed, wouldn't this be a cat-killer?
coprocephalous, Dec 05 2008
  

       i never bought into the uncertainty principal way of looking at it.
WcW, Dec 05 2008
  

       Maybe i should ask father christmas for another perspective on the electronic atomic world . Another independent dimension that can give some hard data . Maybe it would show the pigeons .   

       Aside: Can neutrons be spray painted(slowed and stopped) into large plaques ?
wjt, Dec 06 2008
  

       no.
WcW, Dec 06 2008
  
      
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