Perovskites, named after a mineral discovered in the Urals in the 19th century, are compounds with the chemical formula ABX 3, where A and B are positively charged metal ions and X is a negatively ...
Since the launch of the Crossword in 1942, The Times has captivated solvers by providing engaging word and logic games. In 2014, we introduced the Mini Crossword — followed by Spelling Bee, Letter ...