bonded or not, and is therefore merely used as an indication of the relative sp2-sp3 ratio.) Although the characterization of amorphous carbon materials by the sp2-sp3 ratio may seem to indicate a one-dimensional range of properties between graphite and diamond, this is most definitely not the case. Research is currently ongoing into ways to characterize and expand on the range of properties offered by amorphous carbon materials. 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. Q-carbon Q-carbon, short for quenched carbon, is claimed to be a type of amorphous carbon that is ferromagnetic, electrically conductive, harder than diamond, and able to exhibit high-temperature superconductivity. 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. They have published numerous papers on the synthesis and characterization of Q-carbon, but years later, there is no independent experimental confirmation of this substance and its properties. According to the researchers, Q-carbon exhibits a random amorphous structure that is a mix of 3-way (sp2) and 4-way (sp3) bonding, rather than the uniform sp3 bonding found in diamonds. Carbon is melted using nanosecond laser pulses, then quenched rapidly to form Q-carbon, or a mixture of Q-carbon and diamond. Q-carbon can be made to take multiple forms, from nanoneedles to large-area diamond films. The researchers also reported the creation of nitrogen-vacancy nanodiamonds and Q-boron nitride (Q-BN), as well as the conversion of carbon into diamond and h-BN into c-BN at ambient temperatures and air pressures. The group obtained patents on q-materials and intended to commercialize them. 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. However, their simulations have not been verified by other researchers. See also Glassy carbon Diamond-like carbon Carbon black Soot Carbon References Allotropes of carbon