1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Different types of deuterium?

  1. Nov 14, 2012 #1
    I know you can order deuterium oxide (d2o), but can anyone tell me how I can get different permutations of heavy water? Semi heavy water? And so on....?

  2. jcsd
  3. Nov 14, 2012 #2
    You can't, because hydrogen jumps between the molecules. You know, the H30+ and OH- story.

    So all you can specify is what proportion of deuterium you want - usually sold quite pure, you might dilute it if you really wanted.
  4. Nov 14, 2012 #3
    Dilute it?

    So, if I buy a certain concentration of Deuterium oxide, lets say just for our example its 90% pure d20. This will have a certain molecular vibration (slower than normal water of course since deuterium is heavier)

    NOW....if I dilute it: Will that sample then have a different molecular vibration as the 90% pure d20?

    Basically what I am wanting to get is 2 different samples of a solution containing Deuterium, but with different vibrational frequencies of each sample.
  5. Nov 15, 2012 #4
    Sellers use to offer heavy water D2O of 99%+ purity.

    If you want to have different frequencies in one single batch, mix it with normal water and wait a little; add an acid or heat would save time. You will obtain a mix of D2O, H2O and HDO.
  6. Nov 15, 2012 #5
    What I want is Sample A(Which is D20), Sample B(Which is H20) and Sample C(Which is HDO)

    I can do this by diluting it?

    Each of the 3 samples will have different vibration states. Correct?
  7. Nov 15, 2012 #6


    User Avatar
    Science Advisor

    Even mix of H20 and D20 will have vibration states corresponding to H20, D20, and HDO. You cannot have a pure HDO sample because of water dissociation.
  8. Nov 15, 2012 #7
    So is there no way to have different samples of water and heavy water with different vibrational states?
  9. Nov 15, 2012 #8


    User Avatar
    Science Advisor

    Depends. What's the application? If you are looking at [itex]\gamma[/itex] for water vapor, for example, it will average out, so you can control it by mixing different proportions of H2O and D2O. If you are looking at actual resonant frequencies, however, you'll have all three with different proportions from any mix that isn't 100% one or the other. (Not counting various H3O+ resonances you'll get.)
  10. Nov 15, 2012 #9
    Ok let me try and explain. Please let me know ok? Thanks for great info so far!

    Ok, lets say I want to test Deuterium on a biological system (like a insect)

    My GOAL is to give Sample A to a insect, which I hope to be Deuterium Oxide (d20)

    Then...Give Sample B to another insect, and I want sample B to contain deuterium, but have a different vibration frequency as sample A. So, I was thinking if I had a sample of anything containing deuterium, but different structure.

    Plus sample C would be simply Water (h2o)

    Make any sense?
  11. Nov 16, 2012 #10


    User Avatar
    Science Advisor

    What does vibration frequency have to do with anything? It will make a tiny contribution to a heat capacity, which is a bulk quantity, so heat capacity of different mixes of D2O and H2O will be different.

    The biggest impact on organism is going to be the diffusion rates of water and hydrogen ions. That will also be averaged over a bunch of molecules/ions. So again, you'll get a smooth variation.
  12. Nov 16, 2012 #11
    K^2, tried PM'ing you but ur inbox is full ;)

    Instead of constant bumping of the thread, I thought I would try and PM you, because I really appreciate the info I am getting from you.

    I really hope you can reply to this PM (Promise, I'll stop asking questions lol )

    Let me start from square one. Please correct me if I am wrong in any sense!

    Here is what I plan on doing, and you please tell me your thoughts and any info you can give me to help.

    The plan is:

    We have a couple groups of flies. Now, it has been proven that Deuterium slows down the flies circadian clock! So, I think that different vibrations in the substance given to the fly will react differently with the fly.

    This is why I am trying to figure out how to give the fly some type of deuterium, that has a different vibration.

    Maybe the frequency of the vibration will interact with the cell membrane/receptors. So, possibly the flies receptors act as a key hole, and the substance that has a certain vibrational frequency will fit that key hole better than other substances that have different frequencies.

    But, it has to include some type of Deuterium.

    Does any of that make sense. I know very little about Biology (as you can tell).

    Do you have any suggestions possibly?

    Personally, I think the reason it affects the flies is because Deuterium is simply heavier, so whatever biological mechanism that governs the flies circadian clock will be affect by a slower moving molecule like Deuterium.

    Thanks in advance. Really appreciate it!

    (Please, if I am wrong in any sense, please correct me. I want to learn)
  13. Nov 16, 2012 #12


    User Avatar
    Science Advisor

    Resonant frequencies of water are extremely high. This page has them listed by wave number, k, given in cm-1. To get wavelength use, [itex]\lambda=\frac{2 \pi}{k}[/itex].

    Note that the lowest frequencies are in THz ranges. This is not going to affect any part of biological clock.

    What's going to affect biology is diffusion rates. That's really the only thing that affects timing on scales comparable to timing of various processes. And yes, diffusion rates are related to molecule's or ion's mass.
  14. Nov 16, 2012 #13


    User Avatar

    Staff: Mentor

    And kinetic isotope effect.
  15. Nov 16, 2012 #14
    In which case, sample A would probably mix with the water in the insects body anyway, leading to some form of HDO automatically.
  16. Nov 16, 2012 #15


    User Avatar
    2017 Award

    Staff: Mentor

    @nukeman: Answers won't change even if you open 10 threads with the same question. They might use different words, but D2O simply has one frequency spectrum for each oxygen isotope. HDO has one frequency spectrum for each oxygen isotope, and H2O, too.
    And you need water vapor to see this at all, as liquid water will blur everything.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook