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Why is C-D bond stronger than C-H bond? {D=Deuterium, H=protium}
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+ Inorganic chemistry
+ Chemical bonds
+ Deuterium
+ Chemistry
+ Organic chemistry
Posted by
Michael O'Donnell
Why is C-D bond stronger than C-H bond? {D=Deuterium, H=protium}
Hm. The constant of rotatation for D2, as obtained from rotatation spectra, is 60,86 1/cm, for H2 121,62 1/cm. That is nearly the doubled value. Having in mind, that the mass of an deuteron is twice that of a proton, this is predictable. Hovever, the distance in D2 is seemingly with a tiny difference smaller. Also the mean distance of an electron from the core in a single D should be not exactly the same as in a single H, given, that the mass relation core:electron is doubled in deuterium, thus mass attraction is higher. I found no values of the bond strengths, but I’d assume, that if D2 is more stable than H2 to some extent, these effects were responsible for better geometrical overlap and higher bond energy.
Hm. The constant of rotatation for D2, as obtained from rotatation spectra, is 60,86 1/cm, for H2 121,62 1/cm. That is nearly the doubled value. Having in mind, that the mass of an deuteron is twice that of a proton, this is predictable. Hovever, the distance in D2 is seemingly with a tiny difference smaller. Also the mean distance of an electron from the core in a single D should be not exactly the same as in a single H, given, that the mass relation core:electron is doubled in deuterium, thus mass attraction is higher. I found no values of the bond strengths, but I’d assume, that if D2 is more stable than H2 to some extent, these effects were responsible for better geometrical overlap and higher bond energy.
The difference in electronegativity decides the bond strength. More the electronegativity difference, stronger is the bond. The electronegativity difference is greatest for H-F, so the bond strength will be greatest for this pair.
The difference in electronegativity decides the bond strength. More the electronegativity difference, stronger is the bond. The electronegativity difference is greatest for H-F, so the bond strength will be greatest for this pair.
Hm. The constant of rotatation for D2, as obtained from rotatation spectra, is 60,86 1/cm, for H2 121,62 1/cm. That is nearly the doubled value. Having in mind, that the mass of an deuteron is twice that of a proton, this is predictable. Hovever, the distance in D2 is seemingly with a tiny difference smaller. Also the mean distance of an electron from the core in a single D should be not exactly the same as in a single H, given, that the mass relation core:electron is doubled in deuterium, thus mass attraction is higher. I found no values of the bond strengths, but I’d assume, that if D2 is more stable than H2 to some extent, these effects were responsible for better geometrical overlap and higher bond energy.
Any specialist here with more knowledge?
Yes, there is… Read Mr. Griepenburg’s comment!
Hm. The constant of rotatation for D2, as obtained from rotatation spectra, is 60,86 1/cm, for H2 121,62 1/cm. That is nearly the doubled value. Having in mind, that the mass of an deuteron is twice that of a proton, this is predictable. Hovever, the distance in D2 is seemingly with a tiny difference smaller. Also the mean distance of an electron from the core in a single D should be not exactly the same as in a single H, given, that the mass relation core:electron is doubled in deuterium, thus mass attraction is higher. I found no values of the bond strengths, but I’d assume, that if D2 is more stable than H2 to some extent, these effects were responsible for better geometrical overlap and higher bond energy.
Any specialist here with more knowledge?
Yes, there is… Read Mr. Griepenburg’s comment!
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The difference in electronegativity decides the bond strength. More the electronegativity difference, stronger is the bond. The electronegativity difference is greatest for H-F, so the bond strength will be greatest for this pair.
The difference in electronegativity decides the bond strength. More the electronegativity difference, stronger is the bond. The electronegativity difference is greatest for H-F, so the bond strength will be greatest for this pair.
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VOTE