The shock-tube technique is used to measure the ignition delay time of a lean (phi = 0.5) mixture of n-pentane and air in a wide range of temperatures from 867 to 1534 K and pressures from 11 to 530 atm. The previously developed detailed kinetic model of ignition of hydrocarbons [Kinet. Catal. (2005), in press] is used to interpret the experimental data. The kinetic model includes mechanisms of ignition at high and low temperatures and a mechanism of ignition in the range of intermediate (1000-1200 K) temperatures. Each of these mechanisms is analyzed. The effect of the mixture pressure on the ignition at a temperature of 1000-1100 K is demonstrated. (c) 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved.