Thank you. I have been trying to understand the basics of NMR for past 3 hours and barely got a thing. This video just made the basics so simple and transparent.
I think it's incorrect to say 99.99% nuclei are alligned. in fact the proportions of up/down are darn near equal, with only very small excess alligned with the field in the lower energy state. That's due to thermal Boltzmann energy being way greater (at RT at least) than the difference in energy between the up/down states, causing these states to be filled almost equally.
Svajok You know, this is probably correct, and it wouldn’t be hard to work out using the physics of the situation. The applied magnetic field does create a bias, but it probably is very small. Any physicists out there who want to take a stab at calculating Delta E for a given magnetic field for the proton?
@@mevansthechemist It will vary with "electron shielding" (electrons interfering with the applied polarizing magnetic field), so we'd need to know which nuclei. At one end of the periodic table we have Hydrogen which has an unpaired proton, a nuclear magnetic moment, and not much electron shielding. At the other end of the periodic table is Bismuth, which has a lot, lot of electron shielding and its own unpaired proton in the nucleus. See for example socratic.org/questions/what-is-shielding-and-deshielding-in-nmr-can-you-give-me-an-example
This is what I was looking for, excellent demonstration. Is it possible to make a video about: if we spin a mole of Proton Isotopes what would be the total magnetism B0. Thanks in Advance.
I note that the number of nucleons in the mentioned atoms is odd. Is that because the magnetic dipole moment of even numbered nucleons will cancel each other out and thus not have a net dipole moment. That is not entirely possible for an odd number of nucleons?
That's right, although there are some nuclei with an even number of total nucleons that are still NMR active: those that have an odd number of protons AND an odd number of neutrons, such as deuterium and nitrogen-14. This page has more: chemistry.stackexchange.com/questions/73885/which-nuclei-are-nmr-active.
Hello Mr. Michael, Can you explain why aligned spin has low energy. Actually magnets with same direction should have high energy. What is the direction of B0 in general?
Thanks! You saved my biophysics exam! Amazing explanation
Glad to hear! :-) Thanks for watching.
Thank you. I have been trying to understand the basics of NMR for past 3 hours and barely got a thing. This video just made the basics so simple and transparent.
I think it's incorrect to say 99.99% nuclei are alligned. in fact the proportions of up/down are darn near equal, with only very small excess alligned with the field in the lower energy state.
That's due to thermal Boltzmann energy being way greater (at RT at least) than the difference in energy between the up/down states, causing these states to be filled almost equally.
Svajok You know, this is probably correct, and it wouldn’t be hard to work out using the physics of the situation. The applied magnetic field does create a bias, but it probably is very small. Any physicists out there who want to take a stab at calculating Delta E for a given magnetic field for the proton?
@@mevansthechemist It will vary with "electron shielding" (electrons interfering with the applied polarizing magnetic field), so we'd need to know which nuclei. At one end of the periodic table we have Hydrogen which has an unpaired proton, a nuclear magnetic moment, and not much electron shielding. At the other end of the periodic table is Bismuth, which has a lot, lot of electron shielding and its own unpaired proton in the nucleus.
See for example socratic.org/questions/what-is-shielding-and-deshielding-in-nmr-can-you-give-me-an-example
This is what I was looking for, excellent demonstration.
Is it possible to make a video about: if we spin a mole of Proton Isotopes what would be the total magnetism B0. Thanks in Advance.
Much knowledge in a very little time
That’s always my goal, Abhinaba! 😂
Nice
super helpful thank you!
Thanks, Danielle! Best of luck on your pre-med journey and check back if you need to brush up on organic chemistry! :-)
I note that the number of nucleons in the mentioned atoms is odd. Is that because the magnetic dipole moment of even numbered nucleons will cancel each other out and thus not have a net dipole moment. That is not entirely possible for an odd number of nucleons?
That's right, although there are some nuclei with an even number of total nucleons that are still NMR active: those that have an odd number of protons AND an odd number of neutrons, such as deuterium and nitrogen-14. This page has more: chemistry.stackexchange.com/questions/73885/which-nuclei-are-nmr-active.
Hello Mr. Michael, Can you explain why aligned spin has low energy. Actually magnets with same direction should have high energy. What is the direction of B0 in general?
Never give up 💪
Wooooow
Please speak in Hindi
Am I weird if I'm seeing sexuality out of the explanation? 😄