“Mercury’s liquid state results almost entirely from relativistic effects, said Peter Schwerdtfeger, a quantum physicist at Massey University in New Zealand. Toward the bottom of the periodic table, the electrons in the heaviest elements experience such strong attraction to the atomic nucleus that they move close to the speed of light. At this point, they no longer obey the laws of classical physics, and the resulting quantum phenomena — known as relativistic effects — lead to surprising physical properties. How these manifest depends on the element…”
This is…not how I would word things. Atomic physics is usually not in a classical (Newtonian) regime, and a quantum treatment is standard.
Adding relativistic effects to the quantum treatment is also standard, but many aspects of e.g. the hydrogen atom are reasonably well described without relativistic effects, though of course relativistic effects do matter.
Nitpicking aside, neat stuff!