Nuclear quadrupole resonance spectra,

Fig. 88. 27A1 Fourier transform pure nuclear quadrupole resonance spectra of potassium, ammonium, and mixed alums (428). The pair of high-frequency lines in the mixed sample (56 mol % potassium alum, 44 mol % ammonium alum) clearly indicates the existence of two distinct 27A1 lines.

Nuclear Quadrupole Resonance Spectra Database, Japan Association for International Chemical Information, Tokyo (2003). 

Spectroscopic Properties of Inorganic and Organometallic Compounds, ed. N. N. Greenwood, vols. 1 (1968), 2 (1969), 3 (1970). Each volume surveys the literature of the year before publication, under seven main chapter headings Nuclear magnetic resonance spectroscopy Nuclear quadrupole resonance spectra Electron spin resonance spectroscopy Microwave spectroscopy Vibrational spectra Electronic spectra and Mossbauer spectroscopy. 

CHE/BRO] Cheng, C. P., Brown, T. L., N nuclear quadrupole resonance spectra of coordinated thiocyanate, J. Chem. Soc. Chem. Commun., (1977), 599-600. Cited on pages 232, 380. 

Blinc R (1975) Double resonance detection of nuclear quadrupole resonance spectra. In Smith JA (ed) Advances in Nuclear Quadrupole Resonance, Vol 2, pp 71-90. London Heyden. 

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