Table 4 Reconstructions of W&N’s Lemon (LY1a), Citron (CY1a) and Strontian (SY1a) yellow pigments: pigment composition, Raman and infrared characteristic bands [12, 13, 22, 28,29,30] (the main bands appear in italic)
From: Barium, zinc and strontium yellows in late 19th–early 20th century oil paintings
Pigment composition | Lemon yellow (LY1a) | Citron yellow (CY1a) | Strontian yellow (SY1a) | |||
|---|---|---|---|---|---|---|
BaCrO4 orthorhombic | 4ZnCrO4·K2O·3H2O monoclinic | SrCrO4 monoclinic | ||||
Infrared bands (cm−1) | ||||||
ν(OH) | – | 3442 | – | |||
νas(CrO4 2−) | 885 | s | 881 | s | 911 | s |
855 | sh | 951, 809 | sh | 888, 874, 843 | sh | |
Raman bands (cm−1) | ||||||
δ(CrO4 2−) | 349, 360, 403, 427 | w–m | 342, 408 | w–m | 338, 348, 374, 400 | w–m |
νs(CrO4 2−) | 862 | s | 872 | s | 866 | s |
νas(CrO4 2−) | 872, 898, 906 | w–m | 892 | sh | 894 | m |
940 | m | 916, 930 | w–m | |||