Thanks for Moore Thaung for a very interesting article of new chemistry. Unfortunately, a subscription to New Scientist is required. One can however find in the web several popular articles telling about the changing views of chemical bonds.
This weird chemical bond acts like a mash-up of hydrogen and covalent bonds tells about hybrids of hydrogen and and covalent bonds. For short bond lengths these bonds become strong valence bonds and for long bond lengths weak hydrogen bonds which can even have length of 3 Angstrom.
Strange bonds entirely new to chemists predicted in ammonia hydrides tells that ammonium NH3 can form in the presence of hydrogen in very high pressure an exotic compound NH7, which can decay to NH4+ + H2+ H. NH4+ is also exotic.
Sticking together: Another look at chemical bonds and bonding discusses the theory of chemical bonds proposed by Prof. David Brown, which has turned out to be very successful. His article Another look at bonds and bonding is published in Structural Chemistry 31(1), 2019.
The bond theory of David Brown
The bond theory of David Brown is of special interest.
TGD view about chemical bonds
I remember the time when I realized that TGD suggests a description of the chemical bond in terms of the space-time topology. Could chemistry books be wrong, was the question, which I barely dared to articulate.
Gradually I learned that chemistry books do not really allow any deeper understanding of chemical bonds. One just says that they follow from Schodinger equation but computational complexity prevents proving this.
TGD indeed implies a revolution in chemistry. Some chemical bonds are accompanied by flux tubes carrying dark particles with effective Planck constant heff>h=6h0. Valence electrons of the less electronegative atom would get to the flux tube and become dark. This leads to a model of valence bonds and the value of heff/h0= n increases as one moves to the right along the row of the periodic table. This implies delocalization of the valence electrons to longer scale scaling like heff2 for the Bohr model and this is essential for the delocalization. This delocalization would be essential for chemistry of valence bonds and for biochemistry in particular.
The article also mentions bonds without electrons. Hydrogen bond is of course an example of such: now it would be a proton that becomes dark and has heff>h. In water one could have a spectrum of heff values with various bond lengths and this would give water its very special properties. Even flux tubes without any particles but creating correlations and correlates of entanglement between atoms involved are possible.
Also heff<h bonds are possible. Randell Mills has found evidence for a variant of hydrogenfor which energies are scaled by factor 1/4: this would mean heff=h/2.
An interesting possibility is that in the past scaled down atoms with heff= h/2 have existed. Could they correspond to most of the dark matter, the primordial dark matter? The strange disappearance ofthe valence electrons of some transition metals in heating has been also known for decades: heating would provide the energy needed to increase he<>ff for valence electrons so that they become dark relative to us?
In biology metabolic energy would be used to increase heff, which serves as a kind of universal IQ as a measure of algebraic complexity.