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The diamagnetic susceptibility of disordered monolayer graphene containing scatterers with long-range potential is calculated in a self-consistent Born approximation. Explicit numerical results are obtained for a Gaussian potential. The results show that the delta-function susceptibility in the ideal graphene is broadened by disorder and that the broadening is determined by the condition that states can be mixed with those at the Dirac point. For charged impurities, the susceptibility exhibits a double-peak structure as a function of the Fermi energy at zero temperature, due to the rapid decrease in effective scattering strength with the increase of the Fermi level.

The density of states and conductivity are calculated for scatterers with nonzero range in monolayer graphene within a self-consistent Born approximation. For scatterers with a Gaussian potential, the minimum conductivity at the Dirac point remains universal in the clean limit, but increases with disorder and becomes nonuniversal for long-range scatterers. For charged impurities, we use the Thomas--Fermi approximation for the screening effect. The conductivity increases in proportion to the electron concentration in agreement with experiments and the minimum conductivity becomes about twice as large as the universal value.

1,8-Diphenyl-1,8-bis(diazo)-octa-4-ene-2,6-diyne was prepared and photolyzed to give 1-phenyl-1,3-butadiyne in high yield. Ethynylphenylcarbene and β-phenylethynylcarbene generated by photolysis in MTHF at 6 K are in equilibrium in which the latter predominates at 90 K.