Laser-ablated Ga, In, and T1 atoms react with NO during condensation in exc
ess argon at 10 K to give one major product, which absorbs at 1578.5 cm(-1)
for Ga, 1524.9 cm(-1) for In, and 1454.6 cm(-1) for T1. Infrared spectra o
f (NO)-N-14-O-16, (NO)-N-15-O-16, (NO)-N-15-O-18, and mixed isotopic sample
s show that this product is the metal nitrosyl MNO. Density functional calc
ulations provide good agreement for (3)Sigma(-) GaNO and InNO, but higher l
evel MP2 calculations are required to explain the bent structure and decrea
sed N-O frequency for (3)A " TINO. Model DFT calculations are also reported
for Li[NO] and Li[NO]Li.