Volleyballene
Volleyballene is a hypothetical chemical compound that is a new type of 3D hollow molecule composed of carbon and transition metals. The name is a reference to fullerenes.{{cite web|url=https://www.newscientist.com/article/mg22530101-700-volleyballene-puts-a-new-spin-on-buckyballs/|title=Volleyballene puts a new spin on buckyballs|accessdate=30 March 2019|date=25 February 2015|work=New Scientist}} The main feature of these substances is that metal atoms are part of the framework and they are not deposited on the surface of the molecule. The incorporation of the metal atoms avoids their clustering and confers to volleyballene sites to attach hydrogen. Volleyballene was predicted in 2016 by Jing Wang et al.{{Cite journal|title=Sc20C60: a volleyballene|first1=Ying|last1=Liu|first2=Hong-Man|last2=Ma|first3=Jing|last3=Wang|date=June 2, 2016|journal=Nanoscale|volume=8|issue=22|pages=11441–11444|doi=10.1039/C5NR07784B|pmid=26878201|arxiv=1502.03507|bibcode=2016Nanos...811441W |s2cid=205985813 }} A further study based on Density functional Theory (DFT) carried out by Tlahuice-Flores in the same year supports the predicted structure and gives computed Infrared, Raman and UV spectra for its experimental detection.{{Cite journal|title=New insight into the structure of the C60Sc20 cluster: bonding, vibrational and optical properties|first=A.|last=Tlahuice-Flores|date=May 4, 2016|journal=Physical Chemistry Chemical Physics|volume=18|issue=18|pages=12434–12437|doi=10.1039/C6CP01206J|pmid=27105055|bibcode=2016PCCP...1812434T}} The structure is described as one Sc8 cluster holding 12 scandium atoms linked to six C10 units on each face. The chemical formula C60Sc20 is closely related to C80 fullerene and it has a large predicted HOMO-LUMO gap of 1.47 eV.{{cite web|url=https://www.chemistryworld.com/news/volleyballene-nets-a-place-in-the-buckyball-family/9469.article|title=Volleyballene nets a place in the buckyball family|author=Poly Wilson|accessdate=30 March 2019|date=18 February 2016|work=Chemistry World|publisher=Royal Society of Chemistry}} Further hydrogenation of volleyballene is predicted to give a 70-H structure{{Cite journal|title=Hydrogen Storage on Volleyballene: Prediction of the Sc20C60H70 Cluster|first=Alfredo|last=Tlahuice-Flores|date=July 5, 2018|journal=The Journal of Physical Chemistry C|volume=122|issue=26|pages=14971–14978|doi=10.1021/acs.jpcc.8b03067|s2cid=103888863 }} with an adsorption energy of circa −0.11 eV/H2. Moreover, it is expected that the adsorption-desorption reaction can be reached at ambient temperature. Potential use of volleyballenes is hydrogen storage even at ambient conditions.