Distinct magnetic regimes through site-selective atom substitution in the frustrated quantum antiferromagnet Cs 2CuCl 4-xBr x by Cong, P, Wolf, B, De Souza, M, Krüger, N, Haghighirad, A, Gottlieb-Schoenmeyer, S, Ritter, F, Assmus, W, Opahle, I, Foyevtsova, K, Jeschke, H, Valentí, R, Wiehl, L, Lang, M