Beyond Deshielding: NMR Evidence of Shielding in Hydridic and Protonic Hydrogen Bonds

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388963%3A_____%2F25%3A00638120" target="_blank" >RIV/61388963:_____/25:00638120 - isvavai.cz</a>

Alternative codes found

RIV/61989100:27740/25:10258747

Result on the web

<a href="https://doi.org/10.1021/acs.jctc.5c00870" target="_blank" >https://doi.org/10.1021/acs.jctc.5c00870</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.jctc.5c00870" target="_blank" >10.1021/acs.jctc.5c00870</a>

Result language

angličtina

Original language name

Beyond Deshielding: NMR Evidence of Shielding in Hydridic and Protonic Hydrogen Bonds

Original language description

The red shift of the X-H stretching frequency, with a significant increase in intensity of the corresponding spectral band and a downfield chemical shift of hydrogen (deshielding) in nuclear magnetic resonance (NMR) spectroscopy, has traditionally been used as a criterion for identifying X-H center dot center dot center dot Y hydrogen bonds (HBs) where X is the hydrogen donor and Y is the acceptor. However, over the past two decades, it has become evident that certain HBs can exhibit a blue shift in the X-H stretching frequency and may also show a decrease in IR intensity, diverging from classical expectations. In this study, we investigate a wide array of HBs, encompassing both red-shifted and blue-shifted systems, as well as protonic and hydridic HB systems. We focus on understanding the underlying electronic conditions behind the reverse chemical shift effects-upfield shifts (shielding) upon HB formation, challenging the view that hydrogen bonding (H-bonding) typically leads to deshielding. We employ state-of-the-art quantum chemical methods, integrating computed NMR shielding tensors and electron deformation density, in combination with experimental NMR, to probe that phenomenon. The computational findings are thoroughly validated against experimental results. Our research confirms that shielding is also possible upon HB formation, thereby broadening the conceptual framework of H-bonding.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10403 - Physical chemistry

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Chemical Theory and Computation

ISSN

1549-9618

e-ISSN

1549-9626

Volume of the periodical

21

Issue of the periodical within the volume

15

Country of publishing house

US - UNITED STATES

Number of pages

8

Pages from-to

7495-7502

UT code for WoS article

001541348000001

EID of the result in the Scopus database

2-s2.0-105013227350