Experimentally, sp2 to sp3 ratios can be determined by comparing the relative intensities of various spectroscopic peaks (including EELS, XPS, and Raman spectroscopy) to those expected for graphite or diamond.
(This technique requires deciding on a somewhat arbitrary metric for determining whether neighboring atoms are considered bonded or not, and is therefore merely used as an indication of the relative sp2-sp3 ratio.)
All practical forms of hydrogenated carbon (e.g. smoke, chimney soot, mined coal such as bitumen and anthracite) contain large amounts of polycyclic aromatic hydrocarbon tars, and are therefore almost certainly carcinogenic.
[4] A research group led by Professor Jagdish Narayan and graduate student Anagh Bhaumik at North Carolina State University announced the discovery of Q-carbon in 2015.
The researchers also reported the creation of nitrogen-vacancy nanodiamonds[8] and Q-boron nitride (Q-BN), as well as the conversion of carbon into diamond and h-BN into c-BN[9] at ambient temperatures and air pressures.
[11] In 2018, a team at University of Texas at Austin used simulations to propose theoretical explanations of the reported properties of Q-carbon, including the record high-temperature superconductivity, ferromagnetism and hardness.