A good single crystal is often crucial to gain useful data but, speaking out of experience, it is not easy to obtain one during synthesis. During the ECM 2016 in Basel, I was listening to an interesting talk from Bernhard Spingler (University of Zurich) about single-crystal growth. I approached him to gain further in-sight into crystal growth since experience is an important factor. He provided me with most of his contribution during the ECM as well as several other useful resources to share them with the Young Crystallographers. I hope, some of you will find these useful and if you have further suggestions, simply add them in the comments :)
Bernhard Spinglers Presentation from ECM (updated 11.01.17) minus the parts he could not make publicly available. It gives a great overview over several techniques for those who want to try out something new.
P. G. Jones Chem. Brit. 1981, 17, 222
P. van der Sluis et al. J. Appl. Crystallogr. 1989, 22, 340
J. Hulliger Angew. Chem. Int. Ed. 1994, 33, 143
B. Spingler et al. CrystEngComm 2012, 14, 751
A. J. Blake www.nottingham.ac.uk/~pczajb2/growcrys.htm
Paul D. Boyle xray.chem.uwo.ca/crystal_growing/GrowXtal.html