## 3 Results
### Principal Components Analysis and Cluster Analysis
The =CH\({}_{2}\) in plane deformation vibration was not found as a separate band near 1410 cm\({}^{-1}\), and was most probably hidden under the \(-\)CH\({}_{3}\) and =CH\({}_{2}\) absorption bands. The presence of a =CH\({}_{2}\) group may also explain why the 1330-1410 cm\({}^{-1}\) intensity is higher for some terpen [22]. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Family** & **Species** & **ATR-IR Peaks** & **Compound Assignment** \\ \hline \multirow{8}{*}{Lamiaceae family cluster} & Organo (terpineol, type), age, & \multirow{4}{*}{\(\
eg\)CH\({}_{2}\) in plane deformation at 1420 cm\({}^{-1}\)} \\  & leemon myriffe, & & (presence of \(\
eg\)CH\({}_{2}\) group will increase intensity of the peaks from 1330-1410 cm\({}^{-1}\) for some terpen) [23]. \\  & rosemary plus, & & \(\sim\)1375 and 1450 cm\({}^{-1}\) \\  & (cineol type), & & Peak at \(\sim\)1450 cm\({}^{-1}\) is a result of overlap of CH\({}_{2}\) deformation and asymmetrical CH\({}_{3}\) deformation (intensity of this peak is proportional to the number of CH\({}_{2}\) and CH\({}_{3}\) groups present) \\  & & & \\  & and lavender & & & groups present) \\  & & 3400-3500 cm\({}^{-1}\) & \\  & & (broad band) & Lamiaceae family plant extracts have a higher content of phenolics (and flavonoids). \\  & & 842 cm\({}^{-1}\) (shifted to & Weak skeletal vibration for isopropyl (R\({}_{2}\)C=CH\({}_{3}\) out-of-plane deformation of \\  & & 862 cm\({}^{-1}\) in oregano) & non-strained, weakly strained (cytochrome derivatives) and strongly strained systems); \\  & & 1635-1650 cm\({}^{-1}\) & & key characteristic peak for carved coconts at 862 cm\({}^{-1}\) \\  & & (low intensity peaks) & Vibration for RHC=CH\({}_{2}\) (linalool and linalool acetate). \\  & & 1745 cm\({}^{-1}\) & Carbonyl stretching from \(\alpha\)-thione and campber (age essential oil) \\  & & Double bands at 1370 and 1380 cm\({}^{-1}\) from isopropyl group (tetrahydrodinalool, \\  & & & betrathyographized and their acetates). \\  & (phenol type), & 1458 and 1380 cm\({}^{-1}\) & gem dimethyl [\(\Diamond\)-[C[H\({}_{2}\)]]] in a- and \(\beta\)-pinene band at 1385 cm\({}^{-1}\) could be related to \\  & & & bending symmetry CH\({}_{2}\)(CO) vibration of 1.8/cineo \\  & & \(\sim\)810 cm\({}^{-1}\) & C-H out-of-plane bending for carved (organo); ring vibration of thymol is seen at 807 cm\({}^{-1}\), while for carved coconts corresponding signal appears at 811 cm\({}^{-1}\) \\ \multirow{4}{*}{Asteraceae family cluster} & Echina, & \multirow{4}{*}{\(\
eg\)Liniaga, \(\
egFigure 3: ATR-FTIR spectra for (**a**) Lamiaceae cluster with positive correlation (lavender, lemon myrtle, oregano terpineol type, peppermint, rosmary cineole type, rosmary plus and sage essential oils); (**b**) lavender against Lamiaceae cluster with negative correlation (oregano phenol type, and thyme); (**c**) Asteraceae cluster (chamomile, echinacea, marigold and tagetes) and (**d**) mixed oil samples cluster (arnica, primrose and frankinense). The CH\({}_{2}\) deformation and asymmetrical CH\({}_{3}\) deformation appear at 1450 cm\({}^{-1}\), while the symmetrical CH\({}_{3}\) deformation is near 1380 cm\({}^{-1}\). Although the two 1450 cm\({}^{-1}\) vibrations actually occur at two different frequencies (1460 and 1440 cm\({}^{-1}\) as average values), the two peaks usually overlap and only one peak is observed. The integrated intensity of this band can supply information about the number of CH\({}_{2}\) and CH\({}_{3}\) groups present. The strong band at 1745 cm\({}^{-1}\) for rosmary essential oil, especially in the rosmary cineole type, suggests the presence of 1,8-cineole [12]. For age essential oil, the carbonyl stretching band at 1745 cm\({}^{-1}\) indicates the presence of \(\alpha\)-thujone and camphor [25]. Oregano (phenol type) and thyme essential oils, although in the same group, were separated from the other Lamiaceae plant essential oils. The loading plot for oregano and thyme suggested the importance of the FTIR area around 1380 cm\({}^{-1}\).