Predicting Bond Enthalpy Trends for Atom-Hydrogen Bonds

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The discussion centers on identifying trends in bond enthalpy, specifically for atom-hydrogen bonds, based on calculations performed using Gaussian software. Participants note that while the original poster seeks a trend, the calculated bond enthalpies should provide insights into any existing patterns. It is suggested that for main group elements, bond dissociation energies (BDEs) typically decrease down the periodic table and increase across it. In contrast, for transition metals, M-H BDEs tend to increase down the periodic table, but a clear trend across the periodic table is less evident. A reference table is provided to assist in understanding these trends.
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Is there a period trend for bond enthalpy? Specifically Atom-Hydrogen bonds. Need to find a trend in predicting the bond enthalpy of several atom-hydrogen bonds I calculated using gaussian.

Any help would be appreciated, thanks!
 
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ReidMerrill said:
Need to find a trend in predicting the bond enthalpy of several atom-hydrogen bonds I calculated using gaussian.
If you calculated the bond enthalpies, wouldn't you be in a better position to tell us the trend, rather than us telling you?
 
TeethWhitener said:
If you calculated the bond enthalpies, wouldn't you be in a better position to tell us the trend, rather than us telling you?
I just wondered if there was supposed to be a trend since they don't appear to follow any pattern.
 
Try this table. https://labs.chem.ucsb.edu/zakarian/armen/11---bonddissociationenergy.pdf

For maingroup elements, E-H BDE's are fairly predictable: decrease down the periodic table, and increase across the periodic table.
For transition metals, M-H BDE's increase down the periodic table (1st < 2nd < 3rd). There's not really a clear trend across the periodic table.
 
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